Tagging version 0.99.0.

Remarkable changes:
 - The architecture switched to an implicitly shared data implementation rather than a pointer-based implementation
 - Added compatibility mode for polkit<0.98
 - Improved CMake logic
 - Installation of Config.cmake files

This release has been brought you by Dario Freddi, Jaroslav Reznik and Radek Novacek, and it's meant to be used with KDE>=4.6