Merge pull request #79 from kissge/master

Fix appearance of tool tip
Fix load behavior of retweets.
(re)Fix appearance of tooltips in the inputbox.
Improve code quality.

Fix starting geolocation service.
Fix binding mistake.
Change setting behavior.
Fix crashing when database is locked.
Add debug code for VMHR.
Add handler of attach image from clipboard.
Increment revision.
Improve performance of database accessing.

Show warning when execution property has changed.