Apply MSVTK style to code

* 2 space for indentation
* prefer ```SafeDownCast``` to reinterpret_cast/static_cast
*  Use Superclass to mother class calls
*  Prefer pre-increment  over post-increment (```++i``` instead of ```i++```)
* ```#ifndef```/```#define``` follow the convention ```__filename_h```
* Add space after ```if``` and ```for```

Issue #14
Merge branch '14-msvVTKButtons-cleanup'

* 14-msvVTKButtons-cleanup:
  Apply MSVTK style to code