[TEST] Fix SimpleThreadPoolTests to exclude test infra threads
[BUILD] skip bwc version check if directory doesn't exists or is not a directory
Reflect that 'field_value_factor' is only in 1.2.x

While the blogpost http://www.elasticsearch.org/blog/2014-04-02-this-week-in-elasticsearch/ states, that feature #5519 was
added to 1.x, the release notes for, e.g. v1.1.2, however tell otherwise.
Only the release notes for 1.2.0 list #5519 as a new feature.

Since the 1.x docs deprecate/discourage from using `_boost`, and seemingly give a migration example at
http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/mapping-boost-field.html#function-score-instead-of-boost
users of 1.1.x should be warned.
[DOCS] clarify /_cat/fielddata REST api documentation
Add version 1.2.4 and 1.3.1 to the version table
Docs: Update query-string-syntax.asciidoc

Closes #6253
[DOCS] move all coming tags to added in master
Update named-queries-and-filters.asciidoc
[doc] Correct decay function equations in function_score description

Impact of decay and scale was missing from the equations.

Closes #6983
Fielddata: Fix the ordinals impl for sparse fields.

Caused by #6908
[DOCS] Fix nested root object indexing documentation

Types can no longer be specified when indexing, see:
https://github.com/elasticsearch/elasticsearch/pull/4552