Add a test establishing that blue-style logins, where the username for
login differs (by more than alphabetic case) from the username base32
encoded in the URL, are handled properly.
Refine the provision that refuses the server's acceptance of logins with
usernames that differ from the official username by alphabetic case, so it
only refuses that difference.  It must accept other variations, to allow
for blue-style logins where the login username and username base32-encoded
in the URL are completely different.
Merge pull request #266 from SpiderOak/issue-265-blue-login-problem

Issue 265 blue login problem