Skip committing image instance when loaded image is empty.
refresh database structure.
Fix: Collection change event is not treated correctly in ScrollLockBehavior.
Support in-memory database mode.
Suppress notifications of old tweets.

Change notification interface.
Increment revision.
Fix: vacuuming in transaction.
Improve layout rounding of timeline.

Fix: warning is shown up in tab configuration flip viewmodel.
Fix: char-references on user desription(bio) is not resolved.

see: #105
Improve timeline scroll behavior.
Add timeout to image loader.
Add compact multiline mode.
Attach image via shortcut key(Ctrl+V).
Input completion accepts completion with Tab key.

Close #104.
Improve timeline display.

* Show recipient in direct message (Close #103)
* Show retweeter icon in retweet status
* Show recipient icon in direct message
* Add key assign "ShowRecipientProfile"
Close #43: Add context menu to query editor.
Fix freezing when attaching image.
Fix threading model.
Update mahapps.metro library.

Fix: Application icon is not refreshed when changing application theme.
Update dependent libraries.