Sort results of JavaSearch command using a new Eclim setting.

Setting name: org.eclim.java.search.sort

Testing:
- Updated WorkspaceSettings
org.eclim.java.search.sort=["src/main", "src/test"]

- Ran :JavaSearch and verified that the main code is listed before test.
- Tested with just "src/test" and the main code was listed in the end.
- Tested with empty list and the results were interleaved.
Merge commit '8c81555' into java-search-sort
updates for new java search result sorting

- some re-wording/re-formatting of docs on new
  org.eclim.java.search.sort settting
- update the search result sorting to match the head of the project
  relative path of the search result. This ensures the matching always
  occurs at the same place in the file's path. By simply looking for the
  sort key in the full path there is the possibility of false matching
  (ex. if i have a 'test' src folder and a 'test' package).
- fix the command to pull the new setting from the project's settings,
  then fall back to the workspace setting.
- add a unit test.

refs #372