Fixed creep duration bug

Used to crash when duration was set to 0 hrs 0 mins.
Updated map stuff

Can now map all selected creeps.  Also added in checks for gps enabled
when you try to open up a map. Also prepped the code for updating
locations a bit so it'll be easier when the time comes to receive updates.
Added in gps enabled check on resume of map.

If you disable your gps then go back to map, it does a gps enable yes/no
dialog. If you re-enable, you stay in the map.  If you say no, you're
taken back to the main activity.