Started working on a new text viewer to achieve better performance

As the current file viewer suffers from huge delays, before the opened file is actually shown ( up to several seconds ), i've tried to identify the bottleneck, and the bottleneck was WPF's flow document viewer control I've used and because i've tried to prepare the whole document in advance including all highlighting.

Thus I've started writing a new text viewer control on Sunday and it's progressing well. I already can display and scroll syntax highlighted text including colored background highlighting of matches.

And the best thing is, that it performs very well. Opening a file containing 20.000 lines of code with 40.000 matches happens almost immediately and scrolling is smooth and responsive.

I have still to implement mouse cursor hit tests with the displayed text, which is necessary for implementing text selection via mouse and to restore the functionality which has been broken, due to removal of the flow document viewer.