Merge pull request #47 from misodengaku/master

コンシューマーキーに余計な文字が入っていないかのチェック
bugfix: showing incorrect image as thumbnail if image is not available.

close #46
Create theme editor window(but not implemented).

Update setting behavior of themes.
Improve stability of process for completing auto-update.
Pass cancellation token for streaming thread.

Update build number.
Add check of desktop heap size.

Refactor Nightmare WinAPI structure.
Fix users image sometimes look ugly.
Fix blocked users are not properly treated.

close #56
Change error message in automatic updater.

Describe more details than previous one.
Add help link to authorization window.
Update dependent libraries except MahApps.Metro.

Latest version of MahApps.Metro is still unstable, so we decided not to update it.
Implement background image feature.
Add configuration for storing database file into another path.
Add setting for transparency of background image.
Implementing theme system...

Update theme definition.
Implement(ing) ResourceDictionary generator.
Update MahApps.Metro library.

Implementing theme system...
Change p/invoke method signature.
Implement "Attach Image from Clipboard".
change word of attach menu.
Add MahApps.Metro as submodule.