Debug logging of normal behavior

Add some debug-level logging for the non-error codepaths to help
diagnose issues which don't manifest as errors.

Signed-off-by: Kevin Locke <kevin@kevinlocke.name>

Conflicts:
	en-GB.plg_authentication_mailbox.ini
	mailbox.php
Bump copyright year

Now that we have copyrightable changes in 2014.

Signed-off-by: Kevin Locke <kevin@kevinlocke.name>
Prepare for release of 1.0.8

Update the versions and changelog in preparation for releasing the
current version.

Signed-off-by: Kevin Locke <kevin@kevinlocke.name>

Conflicts:
	mailbox.xml