calculate spill slots for each register class separately

removed unused function

add Projs to CopyB for constraints

fixed LEA DBG statistic call

fixed number of scheduled nodes statistics
slightly adjusted node statistics

removed the old ilp based spiller and the appel spiller (which was never finished and probably never will)

psi transformation constants are now transformed after the psi phase

  - separated constant placement and reference mode changes
  - place constants now in "optimal" block (smallest user dominator)
removed some unused variables

loads are a little bit more expensive than reloads because they have a lower probability to be in the cache