Support simple ${project_path} syntax in options
fixup! Support simple ${project_path} syntax in options

Since Sublime Text 2 provides no project file path information from
window, we have to figure it out by checking each fodler in window.folders()
and return the first folder that contains a .sublime-project file as our
best guess.
Merge pull request #207 from jjgod/master

Support simple ${project_path} syntax in options