Enable Save when widgets have been changed
Merge pull request #4 from kmac5/comp_settings

Enable File->Save menu item when Composition Settings Dialog widgets have changed
Added a signal to image_format_widget and use it to connect to the comp settings dialog.
Added undo to comp settings dialog
Minor fixes & formatting
some cleanup and formatting
Minor changes.
fixed duplicate nodes crash
Include frame_rate with the set of values saved with a composition
Merge pull request #6 from kmac5/frame_rate

Include frame_rate with the set of values saved with a composition
Added KEY_C command to center all or selected nodes in composition view
Fixed a pair of unintentional whitespace edits
Added "F" keyboard shortcut to frame all or selected nodes
Added mouse scroll wheel zooming
Implemented common nodes_bounding_box with Imath::Box2f
Update keyReleaseEvent
Added mouse wheel zooming and image centering
Added Frame Image shortcut
Added About dialog
Fleshed out go_to_project_website() with link to http://ramencomp.blogspot.com/
Code cleanup
ignore devel branch submodules