Added Gitter badge
Merge pull request #117 from gitter-badger/gitter-badge

NEW: Add a Gitter chat badge to README.md
FIX: Remove format.escapeAndEncode method, and replace with encodeURIComponent where appropriate
NEW: Update the version of Solr to 4.9.1 used in travis.ci.
FIX: Only escape && and || and don't escape spaces
FIX: Update request module to the latest version available 2.49.0.
FIX: Use molivawe travis-solr script before multicore option was a default to start Solr.
NEW: Add migration instructions between 0.4.x and 0.5.x.
RELEASE: v0.5.0
BLUP: Regenerate documentation from scratch.
FIX: Update docs since release of v0.2.0
NEW: Add google analytics ID.
NEW: Create a Makefile to generate docs.
FIX: Correct doc of the method rangeFilter.
FIX: Change src of the unofficial github buttons.

Should avoid pop-up with the message "For security reasons framing is not allowed."
FIX: Merge typo fix.
NEW: Update contributors list.
NEW: Update contributors list
NEW: Update the docs with the method #createAddStream().
NEW: Update documentation.