Ignore Mac OSX Finder files
Manage the "offset" input config option
Add input config to change yaw with shoulder buttons
Support paramater update callbacks in cfheadless.
Merge branch 'ps4-shoulder-buttons' of https://github.com/debona/crazyflie-clients-python into debona-ps4-shoulder-buttons

Conflicts:
	lib/cfclient/utils/config_manager.py
	lib/cfclient/utils/pysdl2reader.py
Merge branch 'cfheadless_param_update' of https://github.com/cstanke/crazyflie-clients-python into cstanke-cfheadless_param_update
Merge branch 'cstanke-cfheadless_param_update'
Updated mac ports instruction in README.md