[TEST] Better fix for missing create spec

create is a shortcut to index with op_type=create that the clients support
Reference docs fixes

* Make it clearer that `aggs` is an allowed synomym
  for the `aggregations` key
* Fix broken example in for datehistogram, `1.5M` is
  not an allowed interval
* Make use of colon before examples consistent
* Fix typos
Added base Request class for read operations that usually happen on the master but can be executed locally.
Added base TransportAction class for master read operations that execute locally or not depending on the request class (local flag).

Added support for local flag where missing, in a backwards compatible manner:
     - IndicesExistsRequest
     - GetAliasesRequest (get alias api, aliases exist api)
     - TypesExistsRequest
     - GetIndexTemplatesRequest (get template, template exists)
     - GetSettingsRequest
     - GetRepositoriesRequest
     - PendingClusterTasks

 Added parsing of the local flag where missing in Rest*Action.

 Updated SPEC adding local flag param where missing and added REST tests that contain use of the local flag where it was just added.

Closes #3345
master_timeout parameter is now taken into account when calling cluster pending tasks api through the REST layer

Closes #4806
[TEST] Added missing newline at end of YAML test file
[TEST] Added missing \n at end of YAML files, quoted * and fixed indentation
Accept the same boolean values in RestRequest

Added `no` as a possible value to `paramBooleanAsOptional`, also reused existing code from `Booleans.parseBoolean`

Closes #4808
Return `MatchNoDocsQuery` if query string is emtpy

Closes #3952