Bugfix: Last sheep's notes remain if sheep with no notes looked up

Publish an empty notes list if the sheep doesn't have any notes.
Implement drug list on Lookupsheep

Add drug list. Squash a couple bugs.
Convert layout to use RelativeLayout;
Should work on arbitrary device sizes.
Keep buttons from being pushed off the bottom.
Tested on phone and 7" tablet.
Bugfix: no currently available wormer crashes mgmt

Sheep_management sets wormer_spinner assuming there is a wormer
to be used. User may be out of wormer, causing crash
Merge ../LambTrackerMobile-local

Merge all my local work.