GCS: fix for TLMap crash on OSX 10.9

For some reason home circle was crashing, going back to previous
code.
GCS: fix font centering for OSX 10.9

A known bug makes the letters not appear centered in the
horizontal axis.
GCS: disable modelview on OSX

This is causing crashes on Maverick. Fixing this isn't a huge
priority because it is removed for Qt5 anyway, but it would
be nice if someone did. A complete description of the crash
can be seen here:
Merge pull request #1009 from peabody124/osx_109_fixes

OSX 10.9 fixes
tools: updated astyle svn repository url
Sensors: create method for registering the gyro rate

This s used by the individual drivers to register
their max rate and later the sanity check code for
verifying the settings.
SanityCheck: check the stabilization rates

Only allow rates that are within 85% of what the gyro can track are
permitted.
SanityCheck: monitor for changes in stab settings
SanityCheck: add a new message for unsafe rates
Merge pull request #1016 from lilvinz/fix_astyle_url

tools: updated astyle svn repository url
Merge pull request #1013 from peabody124/safe_sensors_rate

Safe sensors rate