Make particle system update/render toggleable, fix GCC compile warnings.
Merge pull request #728 from ey6es/master

The particle system is killing the frame rate, so let's make it toggleable.  Also fixed GCC warnings.
Merge remote-tracking branch 'upstream/master'
Remove rendering of your own avatar's lookatVectors. This fixes the
behavior where if you are moving and jumping, you will occasionally see
your own lookatVectors on your screen.