Ignore .loc files.
Merging contributions from Sarah and Chris.
Moved Andreas's name to new acknowledgments section.

Also added Sarah's name, and corrected a couple of ill-placed
commas. (What I was taught is that "as well as" is a conjunction like
"and", and follows the rule that it is OK to put a comma before the
conjunction, but not after it.)
Resolving conflict with Gary's edit.