Added water tower and telecom tower to entity prototypes

git-svn-id: https://simjr.googlecode.com/svn/trunk@230 56382930-1720-11df-aca2-1133b060dc17
(1) AbstractSimulationAction objects can now specify a submenuId by
overriding getSubmenuId(). This allows actions to group themselves
under submenus in the context menu.

(2) Multiple labels can now be added to an EntityShape.

git-svn-id: https://simjr.googlecode.com/svn/trunk@231 56382930-1720-11df-aca2-1133b060dc17
(1) EntityShape labels can now be created with your choice of background
color.

git-svn-id: https://simjr.googlecode.com/svn/trunk@232 56382930-1720-11df-aca2-1133b060dc17
Sync'ed with SVN