Make lines shorter and docstrings standardised
Primarilly cosmetic fixes in that:
- long lines are broken
- docstrings are remade using tripple-duble quotes
- docstrings are added
- some commented out legacy code was removed
- "a += x" is used instead of "a = a + x"
Change-Id: Ib5f131e8ba8c72c0f6867dc68f01fcb34e57309e