commitmonitor Code

* add an empty line after the license header
* remove unneeded empty lines at the end of files
* use the right case for the includes
* always use <> for system headers
* update ext/Versions.txt

convert tabs to spaces.

Use updated base classes from TortoiseSVN.

Indicate the GPL license.

Set the window title of the diff viewer according to the diffed project and revision.

* move the resource.h file into the resources folder
* Implement the diffing of revisions

Add a hidden 'main' window which handles the window messages and the icon in the tray area.