Improve use of whitespace on tablets

1) Remove collapsible heading rule
Introduced for T43401 this no longer seems to be needed
now that we do not support Blackberry's and infoboxes can
be floated within articles and is now creating a reflow

This addresses issues with floating on the United States
and Taiwan page.

2) Allow table's to float in tablet.
Only disable floats on mobile resolutions.

Bug: T193418
Change-Id: I64748e08516e1be4b53af22b6897560b7fc87632

skinStyles/mobile.toggle/minerva.less

@@ -16,10 +16,4 @@
 			font-size: @indicatorFontSize;
 		}
 	}
-
-	.collapsible-block {
-		// bug 41401 - without this content doesn't always take up whole width
-		max-width: 100%;
-		overflow: hidden;
-	}
 }