kiji-scoring-server: SCORSRVR-9. ModelRepoScannerServlet should not delete .loc files on startup

issue: https://jira.kiji.org/browse/SCORSRVR-9
review: https://review.kiji.org/r/1669
commit: https://github.com/kijiproject/kiji-scoring-server/commit/a5948ef8d02c7dffae48d3e374cce9951b4a1e93