Merge pull request #8 from lpberg/master

Updated vrpn_Tracker_JsonNet to accept/send text messages

Merge commit 'ba90ec94fe6fd88cb654b34698cb2bbf65127aaf'
Fix #84, accidentally not using the patch in that bug.
Update jsoncpp submodule to avoid static initializers.
Update submodule location for jsoncpp - requires a git submodule sync.
Merge branch 'master' of https://github.com/rpavlik/vrpn
Merge branch 'master' of github.com:lpberg/vrpn