JuffEd 0.5 is started

Yes, I've finally done that: trunk branch now contains development version of version 0.5. What's new? Lots of things.
First of all there are huge architecture changes. Now JuffEd uses a conception of engines, and it will be possible to have documents of different types opened at the same time: plain text, rich text, etc. Each type of documents has its own set of menus and toolbars and its own plugins.
One engine is already implemented: it's a QScintilla engine. It kept all the features from version 0.4 and has a new one: now you can split your document and have two working areas one above another.
One more significant change is that now you can use icon themes installed on your system.
Also I moved to CMake building system (thanks to David Stegbauer from Pardus Linux team), see the file README for building instructions.
Please note that this is a first draft, so there is a list of old features that are not implemented yet, but I'm working on it:
- making a backup copy
- single instance
- checking for external file changes
- auto-saving
- printing
- document reload
- status bar