added timer action
changed map file
more xml tweaks
Merge branch 'towerdefense2.0' of https://github.com/duke-compsci308-spring2013/vooga into towerdefense2.0
fixed tower placement
Merge branch 'towerdefense2.0' of https://github.com/duke-compsci308-spring2013/vooga into towerdefense2.0