Adding ErrorWindow for ReadIn

[Bondoki]

The bfm files violating the standard or if unpredictable problems happen, maybe a additional window with error messages are necessary. Currently, the program just crash:
ToDo:

• replace in main
  catch(std::runtime_error& err){std::cerr<<err.what();} to
  catch(std::exception& err){std::cerr<<err.what();}
• replace in LeMonADEViewer.h
  ReadBfmFile.initialize();
  to

try{
    ReadBfmFile.initialize();
    }
    catch(std::exception& err){std::cerr<<err.what();}

• also for ReadBfmFile.execute()
• delegate all std::err to new error window
• the program should still work and show something, but the LeMonADE-errors should be highlighted as urgent warnings