version 0.6.18 - photos up to 1280x1280, single-column layout support, new version notifications
changed new version message
fixed single-column on retina, fixed save from mediaview
Merge branch 'master' of https://github.com/telegramdesktop/tdesktop
fixed unread loading, fixed map rewrite in new version - 0.6.19
fixed critical bug in msg forward - 0.6.20
changed phrase
fixed crash on contacts without names
Merge branch 'master' of https://github.com/telegramdesktop/tdesktop

Conflicts:
	Telegram/Resources/style.txt
	Telegram/SourceFiles/art/sprite.png
	Telegram/SourceFiles/art/sprite_200x.png
Add ability to drag images from sources (such as Chrome) that only give a URL to a photo.