Opening a sublime-project file when ST2 is closed opens that file for editing

When you open a sublime-project file from Finder (only tested this on OS X) when ST2 is running, it opens it as a project window. But if you do the same when ST2 isn't running, the actual JSON sublime-project file is opened for editing.

Ideally opening a sublime-project file from Finder would always launch the project window, rather than opening the file for editing.