Add ability to run certain packages with assertions disabled

Test can be run with `-Dtests.assertion.disabled=org.elasticsearch`
to run the tests without assertions to make sure assertions
don't hide any assignements etc. that introduce bugs in production.
Packaging: Increasing default for max mapped pages to 262144
Made APIs consistently accept a query in the request body's `query` field.

The following APIs now accept the query in a top level `query` field like:
* delete_by_query
* validate_query
* count

These APIs used to accept the query directly in the request body which was inconsistent with the search and explain APIs. For this reason t

Closes #4074
Allow 'omit_norms'  on the '_all' field

The '_all' field doesn't allow to omit norms. In certain scenarios
omitting the norm values makes a lot of sense to get senseable scoring.

Closes #3734
Made single shards APIs fail if routing is configured to be required in the mapping.

 This change make single shard requests fail when no routing is specified and routing has been configured to be required in the mapping. Thi

 Closes #4506
do not call score() twice
make term statistics accessible in scripts

term statistics can be accessed via the _shard variable.

Below is a minimal example. See documentation on details.

```

DELETE paytest

PUT paytest
{
    "mappings": {
        "test": {
            "_all": {
                "auto_boost": true,
                "enabled": true
            },
            "properties": {
                "text": {
                    "index_analyzer": "fulltext_analyzer",
                    "store": "yes",
                    "type": "string"
                }
            }
        }
    },
    "settings": {
        "analysis": {
            "analyzer": {
                "fulltext_analyzer": {
                    "filter": [
                        "my_delimited_payload_filter"
                    ],
                    "tokenizer": "whitespace",
                    "type": "custom"
                }
            },
            "filter": {
                "my_delimited_payload_filter": {
                    "delimiter": "+",
                    "encoding": "float",
                    "type": "delimited_payload_filter"
                }
            }
        },
        "index": {
            "number_of_replicas": 0,
            "number_of_shards": 1
        }
    }
}

POST paytest/test/1
{
    "text": "the+1 quick+2 brown+3 fox+4 is quick+10"
}

POST paytest/test/2
{
    "text": "the+1 quick+2 red+3 fox+4"
}

POST paytest/_refresh

POST paytest/_search
{
    "script_fields": {
       "ttf": {
          "script": "_shard[\"text\"][\"quick\"].ttf()"
       }
    }
}

POST paytest/_search
{
    "script_fields": {
       "freq": {
          "script": "_shard[\"text\"][\"quick\"].freq()"
       }
    }
}
POST paytest/test/2/_termvector
POST paytest/_search
{
    "script_fields": {
       "payloads": {
          "script": "term = _shard[\"text\"].get(\"red\",_PAYLOADS);payloads = []; for(pos : term){payloads.add(pos.payloadAsFloat(-1));} return payloads;"
       }
    }
}

POST paytest/_search
{
   "script_fields": {
      "tv": {
         "script": "_shard[\"text\"][\"quick\"].freq()"
      }
   },
   "query": {
      "function_score": {
         "functions": [
            {
               "script_score": {
                  "script": "_shard[\"text\"][\"quick\"].freq()"
               }
            }
         ]
      }
   }
}

```

closes #3772
Allow GetAliasRequest to retrieve all aliases

Results in less data being sent over the wire, as the Cat API does not
need to have the whole cluster state.

Also added matchers for hasKey() for immutable open map (I think we should
add more of those to have map style assertions).

Closes #4455
Replaced `ignore_indices` with `ignore_unavailable`, `expand_wildcards` and `allow_no_indices`.

* `ignore_unavailable` - Controls whether to ignore if any specified indices are unavailable, this includes indices that don't exist or closed indices. Either `true` or `false` can be specified.
* `allow_no_indices` - Controls whether to fail if a wildcard indices expressions results into no concrete indices. Either `true` or `false` can be specified. For example if the wildcard expression `foo*` is specified and no indices are available that start with `foo` then depending on this setting the request will fail. This setting is also applicable when `_all`, `*` or no index has been specified.
* `expand_wildcards` - Controls to what kind of concrete indices wildcard indices expression expand to. If `open` is specified then the wildcard expression if expanded to only open indices and if `closed` is specified then the wildcard expression if expanded only to closed indices. Also both values (`open,closed`) can be specified to expand to all indices.

Closes to #4436
Made parsing of ByteSizeValue case independent

This allows to parse '12GB' as well as '12gb'

Closes #4442
Remove GET `_aliases` api in favour for GET `_alias` api

Currently there are two get aliases apis that both have the same functionality, but have a different response structure. The reason for having 2 apis is historic.

The GET _alias api was added in 0.90.x and is more efficient since it only sends the needed alias data from the cluster state between the master node and the node that received the request. In the GET _aliases api the complete cluster state is send to the node that received the request and then the right information is filtered out and send back to the client.

The GET _aliases api should be removed in favour for the alias api

Closes to #4539
remove double check for null in value source
Term Vector settings should be treated like flags without propergation

today if a specific feature is disabled for term vectors with something
like 'store_term_vector_positions = false' term vectors might be disabeled
alltogether even if 'store_term_vectors=true' in the mapping. This depends on the
order of the values in the mapping since the more specific one might override
the less specific on.

Closes #4582
Simulate the entire toXContent instead of special caseing

Today we try to detect if we need to generate the mapping or not in
the all mapper. This is error prone since it misses conditions if not
explicitly added. We should rather similate the generation instead.

This commit also adds a random test to check if the settings
of the all field mapper are correctly applied.

Closes #4579
Closes #4581
s/similariry/similarity in AllFieldMapper
[TEST] Split delete by query tests pre-1.0 and post-1.0

See #4074 for details
[TEST] split tests with parent to pre/post 1.0 in the yaml test suite

See #4506 for details
[TEST] add name parameter to get_alias in update_alias tests

to avoid failure on older es versions since get_alias without name has been
only introduced in #4539
In the spirit of the soon-to-be New Year 2014?
Add field data memory circuit breaker.

This adds the field data circuit breaker, which is used to estimate
the amount of memory required to load field data before loading it. It
then raises a CircuitBreakingException if the limit is exceeded.

It is configured with two parameters:

`indices.fielddata.cache.breaker.limit` - the maximum number of bytes
of field data to be loaded before circuit breaking. Defaults to
`indices.fielddata.cache.size` if set, unbounded otherwise.

`indices.fielddata.cache.breaker.overhead` - a contast for all field
data estimations to be multiplied with before aggregation. Defaults to
1.03.

Both settings can be configured dynamically using the cluster update
settings API.