Addressed issues raised by Nathan and Florian
Addressed issues raised by Nathan and Florian

- Added a comment to clarify supporting branches and cherry-picking
- Added a git snippet for merging the master
- clarified language from the main branch descriptions
- specified where links to the travis and codacy checks can be found
- fixed typo in formatting

QudevETH/PycQED_py3,DiCarloLab-Delft/PycQED_py3,DiCarloLab-Delft/PycQED_py3,DiCarloLab-Delft/PycQED_py3