Remove redundant checkmark icon in Preferences > Skin drop-down menu. Only displays warning icon, if the minimum size of the selected skin is bigger than the screen resolution.
Change wording for warning message, that is displayed below the skin drop-down-menu, if the minimum size of the selected skin is bigger than the screen resolution. Reflects that we have resizable skins now.
Update warning icon displayed in the Skin selection drop-down menu.
Add warning icon to the icon template
Make sure to only set the correct number of vinyl control speed COs
Fixes: https://bugs.launchpad.net/mixxx/+bug/1263468
Merge pull request #130 from esbrandt/lp1081132

Remove redundant icon in Preferences > Interface > Skin drop-down menu