Added doc file processing to update coming/added references

We use 'coming[x.y.z]' in our ref docs which needs to be updated
when doing a release to 'added[x.y.z]' This commit adds support
for replacing the references where applicable during preparing the release.
Resolve aliases on redirects inside TransportMoreLikeThisAction

fixes #4045
Optimize concrete index resolution in TransportMoreLikeThisAction
Remove unreleased versions from master & fix 0.90.6 Lucene Version
Throw an exception if a type's mapping root node is not equal to the type in question.

Also, fix all the problems it brought up in tests.
Removed OverrideTypeMappingTests as it is no longer relevant.
Better naming for the default percolator mapping and change it's content use _default_ as root node.

Closes #4038
Add optional RPM building, signing and uploading to release script
Fix `indices.recovery.concurrent_small_file_streams` not being dynamically settable

Fixes #4094
Dist. Percolation: Use .percolator instead of _percolator for type name
Use .percolator as the internal (hidden) type name for percolators within the index. Seems nicer name to represent "hidden" types within an index.
closes #4090
better support for single value to settings builder where the type gets lost
relates to #4097
Change 'standart' analyzer to use emtpy stopword list by default.

The 'default' / 'standard' analyzer can be a trappy default sicne it filters
english stopwords by default. Yet a default should not be dedicated to a certain language
since elasticsearch is used in many different scenarios where a standard analysis chain
with specialization to english full-text might be rather counter productive.

This commit changes the 'standard' analyzer to use an empty stopword list for indices
that are created from 1.0.0.Beta1 version onwards but will maintain backwards compatibiliy
for older indices.

Closes #3775
Add /_cat endpoint
Make RPM building mandatory

If RPM tools are not installed the release tool now fails with an
appropriate message. The tool now also fails if any of the required
artifacts is not present.
NPE when closing XContentBuilder and using 'pretty' query parameter
fixes #4100
Fixed doc_id used in combination with context.searcher(), needs to be topLevelId rather than just docId

Improved test to catch this problem calling refresh more frequently and having the word to highlight in different positions in the text

Closes #4103
Improved highlight *manyDocs tests (fvh and postings) to have random refreshes, flushes and optimizes using indexRandom
Use same caching strategy for STANDARD and DEFAULT analyzer
Apply fix for LUCENE-5330 pruning the IndexWriter queue to get rid of pending event

Closes #4093
release [1.0.0.Beta1]
move to [1.0.0.Beta2] SNAP
Index Stats: Add support for segments stats
closes #4101