Merge remote-tracking branch 'origin/master' into retina

Conflicts:
	main/external/xwt
	main/src/core/MonoDevelop.Ide/MonoDevelop.Components/GtkUtil.cs
	main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.WelcomePage/WelcomePageRecentProjectsList.cs
	version-checks
Bump md-addins
[Icons] empty-file-32.png → file-generic-32.png (and a new icon)
[Icons] Updating older icons to current versions
[Icons] New class file icon
[Icons] New interface file icon
[Icons] New struct file icon
[Icons] New enumeration file icon
[Icons] New XML file icon
[Icons] text-file-*.png → file-text-*.png (and a new icon)
[Icons] template-16.png → file-template-16.png (and a new icon)
[Icons] resource-file-*.png → file-resource-*.png (and a new icon)
[Icons] md-addins bump
[Icons] Fixing wrong file URI
Updated reference to md-addins
Remove some unused icons
[Icons] Wrong icon registration fixed
[Icons] file-template-surround-with-*.png
[Icons] Status searching cleanup
[Icons] Status pushing cleanup