Core: Remove NestedDocsFilter, because it isn't used and also don't eagerly load it in bitset filter cache.

Closes #8414
Test: MinimumMasterNodesTests.testCanNotBringClusterDown should always set minimum master nodes.
Internal: Inverse DocIdSets' heuristic to find out fast DocIdSets.

DocIdSets.isFast(DocIdSet) has two issues:
 - it works on the DocIdSet interface while some doc sets can generate either
   slow or fast sets depending on their options (eg. whether an OrDocIdSet is
   fast or not depends on the wrapped clauses).
 - it only works because the result of this method is only taken into account
   when a DocIdSet has non-null `bits()`.

This commit changes this method to work on top of a DocIdSetIterator and to use
a black-list rather than a white list: slow iterators should really be the
exception rather than the rule.

Close #8380
[TEST] added Get Index bwc test
[docs] add 2d vis for decay functions and parameters

closes #8420
Docs: Removed old coming/added tags
Scripting: Add score() back to AbstractSearchScript

See #8377
closes #8416
closes #8417
Rest API: indices.delete should have "index" as a required param
Core: add max_determinized_states to query_string and regexp query/filter

This prevents too-difficult regular expressions from consuming
excessive RAM/CPU; the default max_determinized_states is 10,000 (same
as Lucene) but query_string and regepx query/filter can override
per-request.

The also upgrades to a new Lucene 5.0.0 snapshot.

Closes #8386

Closes #8357
remove wrong repository
Internal: extend refresh-mapping logic to the _default_ type

When data nodes receive mapping updates from the master, the parse it and merge it into their own in memory representation (if there). If this results in different bytes then the master sent, the nodes will send a refresh-mapping command to indicate to the master that it's byte level storage of the mapping should be refreshed via the document mappers. This comes handy when the mapping format has changed, in a backwards compatible manner, and we want to make sure we can still rely on the bytes to identify changes.  An example of such a change can be seen at #4760.

This commit extends the logic to include the `_default_` type, which was never refreshed before. In some unlucky scenarios, this caused the _default_ mapping to be parsed with every cluster state update.

Closes #8413
Test: switch to TRACE logging for some components
Test: restore logging to prior state
Query: add option for analyze wildcard/prefix also to simple_query_string query

The query_string query has an option for analyzing wildcard/prefix (#787) by a best effort approach.

This adds `analyze_wildcard` option also to simple_query_string.

The default is set to `false` so the existing behavior of simple_query_string is unchanged.
Refactor term analysis for simple_query_string prefix queries

Also fixes an issue where the token stream could be non-closed if an
exception occured.
[TEST] Disable compression in BWC test for version < 1.3.2

The compression bug fixed in #7210 can still strike us since we are
running BWC test against these version. This commit disables compression
forcefully if the compatibility version is < 1.3.2 to prevent debugging
already known issues.
Docs: Fix incorrect documentation for the `index.query.parse.allow_unmapped_fields` setting.

The `index.query.parse.allow_unmapped_fields` setting can't influence whether unmapped fields are allowed
in alias filters and percolator queries.
Test: dump all threads when delete index fails during test cleanup
Core: still don't load bloom filters, even when Directory instance doesn't have a codecService
Docs: note about confusing disk threshold settings