v2.0.0.12

UI - Improve visual look of the "all" button in the send coins dialog.
UI - Fix a problem with increasing memory consumption over time that was affecting some users.
UI - Fix an issue where emptying an "unlocked" witness account first required restarting the wallet.
UI - Fix an issue where an "unlocked" witness account would show incorrect statistical information.
CORE - Reduce memory footprint and improve performance of witness validation.