UOA: Miscellaneous cleanups.

(cherry picked from commit 5bea95d7e40b3d0955391942890fafd1606bb70f)
UOA: Return IMAP/SMTP user names when collecting user info.

Can't assume the user names are the same as the collection identity.

Would be better to specify this in the .service files.

   e.g. <imapuser>EMAILADDRESS / USERIDENTITY</imapuser>

But that can wait.  Hard-coding by provider is ugly but works for now.

(cherry picked from commit 3fb3ba6bb2400a7805f05ed1a980f33d4122ea60)
UOA: Add support for IMAP access to Windows Live accounts.

Adds a few new translatable strings, with approval from the i18n team.

(cherry picked from commit 8ffb92b8951b25a8f0118ec7463d3a8c249c809a)