Refactor route rendering colors: hardcoded --> config file

Review Request #103314 - Created Dec. 3, 2011 and submitted - Latest diff uploaded

Florian E├čer
Based on the discussion from this patch turns the hardcoded colors in the routing layer into softcoded colors and alpha values that are stored in the config files.
Done for both KDE and Qt-only:
* compile
* start and close Marble --> default values are written to config file (Qt)
* manually edit the config files (~/.kde/share/config/marblerc and ~/.config/ Desktop Globe.conf) and add/change the colors and alpha values there
* start Marble again --> route is rendered in different color

I could only test the default route color. I guess the other two are used while GPS navigating?