Was only possible on startup before, changing the paths required recreating the whole projectM instance. Now, the method will only reset the texture manager, but not the shaders and presets.
Lots of interconnected changes in this commit:
- Removed unnecessary name/author/filename members all over the place.
- Started using exceptions to deliver preset loading and rendering errors to the topmost ProjectM class.
- Added stream loading methods to factories and the base Preset class.
- Added new events for requesting preset switch and telling the user about loading errors.
- Consolidated preset switching logic in ProjectM class a bit.
