made server_url case sensitive
remove trailing slash from server_url before entering in database, make lookup trailing-slash-insensitive
Merge pull request #617 from MartijnR/master

fixes for less common server url variations
added logging to investigate reported issue with localStorage
Merge pull request #618 from MartijnR/master

added more detailed error messages to investigate reported issue with localStorage
Merge pull request #619 from SEL-Columbia/master

see commits