Location parsing for files in the project
Rename retree.py entry in projfile
Remove current_path from the rewrite API

The project file path is passed through. This may then be used by
one of the file rewriter functions defined in the "locations" map.
Option for using "git mv" to rename files
"<absolute>" and "<group>" include the quotes. Xcode!
Location handler for "<group>" file references
move_file() correctly picks up the current path

i.e. top-level-section + entry.path
Log an error on unimplemented file location handlers
Merge pull request #9 from bobrippling/dev

Relative to group, yo