rosapps: add directory structure

Added: trunk/rosapps/cmdutils/
Added: trunk/rosapps/demos/
Added: trunk/rosapps/devutils/
Added: trunk/rosapps/games/
Added: trunk/rosapps/lib/
Added: trunk/rosapps/net/
Added: trunk/rosapps/sysutils/
Added: trunk/rosapps/tests/