Retrieve version from git, post github migration
Protect certain setup parameters with sys.platform

 * Allows setup to run where py2exe is not available
adding ROS files
Handle when creation of version.py is not possible

 * Catkin (non-standardly) builds from outside source dir
improve README.md

- updated command line tools installation instuctions
- updated homebrew installation instuctions
- pip link
- fixed typos
Merge branch 'derhuerst-patch-1'
Merge branch 'ros-hydro' of https://github.com/mchenryc/crazyflie_clients_python into mchenryc-ros-hydro
Merge branch 'mchenryc-ros-hydro'
Trying to receive param updates.'
Merge branch 'master' of github.com:bitcraze/crazyflie-clients-python
Fixed bug. Now reading values.

The connected callback was being held hostage.