Attempting accuracy check of "assigner"

This is a repeat of David's commit 20dfbe7 but with hopefully better
results when merging. Undid change to /plots* in .gitignore (appears
to be a typo).
add LocationManager and rawLocation files

This is a redo of David's commit
67c39d95e29e44a93a215762fb37b522427e5a0a which didn't merge properly
with master.