Add blurb on video thumbnail generation
Fix parsing the backend parameter
Postgres doesn't like 'user' as a columnname.
phpdoc
Metadata data is binary (it may include serialized data) so need to store as binary
Cast msguid to a string, since it may appear as an integer to Horde_Db and won't be quoted correctly

E.g. postgres doesn't allow = with integer columns
[mms] Add support for using Horde_Db as the storage backend for IMAP/POP caching.