PCMSolver Feature: Cleanup svn directory name

The pcm solver feature (eclipse project de.uka.ipd.sdq.pcmsolver.feature) is stored in an svn directory named de.uka.ipd.sdq.context.feature.
To make it more intuitive and to remove some mapping configurations for the build server, the svn directory should be renamed to de.uka.ipd.sdq.pcmsolver.feature and the build definitions (buckminster rmap) should be adapted.