Vienna kdev/kate sprint: kdevelop settings dialog and changes to kdev-python

In an effort to improve the overall quality of KDevelop's user interface, Aleix and I polished the settings dialog of KDevelop. Since the Kate guys challenged us by showcasing their "awesome" gimp skills, I feel like I have to do that too:

Comparison between the old and the new configuration dialog in KDevelop

 There wasn't really any changes to functionality, it's just supposed to look better and be more understandable.

There's also news in kdev-python: The Python 3 version is progressing somewhat quickly, and it might be worth trying it out already! If you want to do that, just checkout the python3 branch, you can use it with kdevelop/kdevplatform master (not 1.4!).

There's two pretty significant (altough mostly internal) changes:

1. The KDevelop hints (like "this function returns a type equivalent to the type of its first parameter") are now stored in comments instead of decorators. This should make it possible to use them in custom projects with less hassle. See the builtindocumentation.py file for examples of what the new syntax looks like, and feel free to suggest new such hints!
2. Python 3 has nice features for annotating functions, you can do something like def myfun(arg: int) -> int: ...
   This is now supported by kdev-python, the annotations will be parsed and added to the duchain. However, this will only happen if your annotation expressions return a type: If you annotate your arguments with e.g. strings explaining what they do, that's fine, kdev-python will ignore them.

Have fun, and, as always: if you find any bugs, report them on the tracker so I can fix them as soon as possible :)