Make execute() and select() abstract, deprecate execute().
Refactor unit tests (again).

Centralize tests as much as possible to help with detecting differences between
the implementations, and for easier code maintenance.
[jan] Don't ping server before each query in PDO drivers (Bug #12656).
Use constant.
Possible fix for Bug: 12647, add missing 'id' attribute to form.
Not used.
phpdoc
We haven't needed this hack/workaround for sometime now. Remove.
typo
This is not always a modseq value, log it accordingly.
Tweak some comments/spacing.
phpdoc
Support sending SOFTDELETE changes to the client.

This commit just supports the sending of the change, does
not implement detecting the changes. That will go in Core.
Some comments while I'm poking around.
[mms] Don't attempt to get quota information from non-IMAP mailboxes (Bug #12608).
Typo
Improved parsing of e-mail address input
Clean-up addresses when saving a draft
Merge branch 'master' into imp_6_2

Conflicts:
	imp/package.xml