We discussed this a while ago, and I believe we agreed that it's more useful to match username, first_name, and last_name queries anywhere in the string(s) instead of just the beginning.

All tests pass aside from a few VCS-dependent ones, which are skipped.
I changed the user WebAPI test to search for the middle of the name ("rum" in "grumpy" instead of "gru").  I didn't bother having both searches, since matching in the middle pretty much guarantees matching at the start.