[FIX] account: partner balance general totals

General totals were not computed at all, due to the condition "if not self.ids" which was always true as self.ids wasn't set.

Besides, a parameter allows to display only partner with balance greater than 0, which was completely ignored by the totals computation methods: The totals always included all partners, even those having balance equals to 0
Revert "[FIX] mail: read more show original message"

This reverts commit 0790682296e43989e4e232189009c3ba380e32ba.

This fix is not yet ready. See PR #3295