Switched to using a compatible CFG-MSG format for newer ublox version (>=5)
Replaced outdated CFG_MSG
[dox] replace backticks by tilde for code block in markdown file

so it works in both doxygen and github
[dox] fix missing tilde
[ahrs] use weak functions for things that don't need to be implemented by each algorithm
Merge pull request #646 from achambers16/ublx_center_compat

Fix compatibility with automatically configuring newer ublox modules
[tools] move attitude_viz from in_progress to tools
[lpc21] actuators_4015: rename SERVO_GAZ to SERVO_MOTOR

closes #613
[tools] move gps ublox config tool

closes #612
cleanup some unused/outdated stuff from in_progress