#439: Add unit test to verify downloading a file authenticated as UserB using a signature generated for UserA fails
#338: Added unit tests for downloading principal pictures and verifying the multiple permutations that parameters can be passed in.
Merge branch 'master' into issue-439

* master: (42 commits)
  Changing grouping for adding members
  Fixed config file
  Minor doc fixes
  #502 - PR followup
  # 502 - Changed the actor and target for group-add-members
  Minor docs fixes
  #502 - Add tenant information to each activity entity
  README fix
  Updating README
  #404 - Resolving path to clean as we cannot output a path with a double slash.
  #500 - Not creating an activity if no text has been editted on publish.
  #500 - Passing the user's language on to Etherpad
  #500 - Fleshes out the Etherpad section in the README
  Minor test clean-up
  code review issues, actually test search, and fix the search
  add test for mime type property
  only add _extra.mime on 'file's
  add mimeType to content searches
  #472 Cleaned up image scaling in the preview processor a bit.
  Change etherpad port to 80
  ...
Merge master in issue-338 (profile pic test coverage).
Merged master in issue-338 (bump in testcoverage for picture cropping).
Setting etherpad defaultPadText to an empty string so tests may succeed.
Add ability to clear a config value on a tenant
Replacing defaultPadText after the settings.json files has been created.
Merge pull request #530 from simong/travisEtherpadDefaultPadText

Setting etherpad defaultPadText to an empty string so tests may succeed.
code review issues
Stopping memcached, mysql and postgresql on travis.
Merge pull request #532 from simong/travisLessMemory

Listing travis services.
Merge pull request #439 from simong/issue-439

Add unit test to verify downloading a file authenticated as UserB using a signature generated for UserA fails
#338 - PR review - cleaned up code.
Merge pull request #510 from stuartf/config-clear

It should be possible to clear a config value on a tenant
simplify validator logic
last manager can't leave a group
Use jshint not jslint for style checking
fix line endings and trailing whitespace
jshint cleanup