Basic support for CodeMirror editor
(at least context menu doesn't work)
(WIP for #17)
Rebranding: rename internal things to match "source editor" and not only "orion editor"
(I hope, all correct here...)
(WIP for #17)
Add support for editor in tab
(WIP for #18)
Bump version to 0.1.0a4pre - 2013-09-26