"Open With" on context menu

It would be nice, if there would be an "edit"-action available within the context menu for files (editor should be configurable)

Use case: Preparing a commit within "File Status" view.
During review process whilst preparing a commit of certain files I review the changes in those files before adding them to the staging area. Often I notice some small things to change (for example incrementing the version number) before I can commit. It would be nice to be able to open those files directly from sourcetree within an external editor. At the moment I have to browse to this file using explorer ("Huh? Where is the file?" ) and open an editor from there ....