Add parser support for HOLD, SUPPORT, CONVOY

    -add command filter

Squashed commit of the following:

commit 9d6a0e9446bbb30e3b3941e2e68968ed9477fb48
Author: Nikola Savic <NikolaSavic@gmail.com>
Date:   Tue May 27 22:59:30 2014 -0400

    Add parser support for HOLD, SUPPORT, CONVOY

    -add command filter