Implement a custom blame viewer.
The viewer shows the blame information on the left, the file contents on the right side.
The blame information is colored so that revisions and authors can be seen grouped.
Also, the corresponding log entries for each line are shown in tooltips.
src/TortoiseBlame : the new project for the viewer
src/Utils/scintilla : the scintilla control for showing the file contents.
Issue : 95