Apex File Properties, Conflicts, Synchonrization, Bug Fixes

* Support for caching of Apex file properties on refresh and save
* Support for overwriting Apex file properties for active and selected
files/dirs
* Support for synchronizing files / dirs with server - **Currently only
supports DiffMerge**
* Support for checking modified date against local cache to prevent
remote files from being overwritten when they change via setting
[mm_check_conflicts_on_save]
* Support for opening of metadata files based on file properties,
allows for CustomObjects to be opened as well as stardard object
CustomFields.
* Bug fix for retrieve_result adding CustomField when not needed
* Bug fix for selecting metadata when indexing, not needed as this is
done before it is displayed
* Loop performance enhancements
Conflict marking in Apex properties

Mark as conflict in apex properties when dates don't match, bug fix for
successful save, rename method
change setting name to mm_compile_check_conflicts
Bug fixes

* Use Popen so that DiffMerge doesn't keep MavensMate running
* Fix for temp files
* Improved parameter checking for synchronize, default to using files
Merge pull request #21 from doublesharp/patch-conflict-synchronize-merge

Patch conflict synchronize merge