Term Vectors: removed Nullable annotation on a primitive type
ParseField: Support for when all fields are deprecated

Closes #8067
Bulk indexing: Fix 8125 hanged request when auto create index is off.
If a bulk request contains a mix of indexing requests for an existing index and one that needs to be auto-created but a cluster configuration prevents the auto-create of the new index the ingest process hangs. The exception for the failure to create an index was not caught or reported back properly. Added a Junit test to recreate the issue and the associated fix is in TransportBulkAction.

Closes #8125
Docs: fixed typo in documentation

Closes #8205
Docs: rolling upgrade process seems incorrect

When reading the [rolling upgrade process](http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/setup-upgrade.html#rolling-upgrades), you can see that we wrote:

* disable allocation
* upgrade node1
* upgrade node2
* upgrade node3
* ...
* enable allocation

That won't work as after a node has been removed and restarted, no shard will be allocated anymore.
So closing node2 and remaining nodes, won't help to serve index and search request anymore.

We should write:

* disable allocation
* upgrade node1
* enable allocation
* wait for shards being recovered on node1
* disable allocation
* upgrade node2
* enable allocation
* wait for shards being recovered on node2
* disable allocation
* upgrade node3
* enable allocation
* wait for shards being recovered on node3
* disable allocation
* ...
* enable allocation

I think this documentation update should go in 1.3, 1.4, 1.x and master branches.

Closes #8218
Closes #7973.