KVHDirveNode performs conditional odometry filtering

A few bugfixes related to typos, and added a conditional check on the
should_odom_filter_ flag for the imuCB that will disable odometry
filtering on command. However, odometry filtering currently doesn't work
properly (it is taking into account rotation now, but quickly goes nan)
due to the covar matrix becoming non positive-definite. This could be
due to linear corrilations between states. For now will leave disabled
by deafult, and open a new issue for futher examination.

Closes #1, closes #13
Merge branch 'master' of https://github.com/RIVeR-Lab/kvh