Move FlattenArchitecture out of AutomaticClusteringHelper into own class.

Add option to only flatten specified amount of levels. Do refactoring of
Flattenarchitecture class.
2 jobs for ML_clustering in 20 minutes and 45 seconds
Status Job ID Name Coverage
  Windows
passed #244838
Windows10
masterJobWindows

00:15:09

 
  Linux
passed #244839
BranchJobLinux

00:05:36

6.0%