Adds support for Desktop Enty's Path
Fixes https://bugs.launchpad.net/linuxmint/+bug/1120639
Changes:
- Added appPath to ApplicationLauncher in easybutton.py
- Added new commandCwd argument to Exec in execute.py (defaults to None)
- ApplicationLauncher.execute() now passes CWD to execute.Exec
Merge branch 'cwd-fix' of https://github.com/xwizard/mintmenu into xwizard-cwd-fix

Conflicts:
	usr/lib/linuxmint/mintMenu/plugins/execute.py