Fixes for expandable documentation

Several fixes for messages with large documentation that is compacted in the message editor:
* CSS property manipulations removed from JS code, just manipulate long and compact classes and let the styling be at the CSS.
* Messages are compacted to a percentage of the current vertical space instead of a fixed size. This provides more space for long messages.
* Long messages use a smaller font size so that more content can be visible.
* "View more" link can be used to make the documentation compact again (TODO: the message should change to "Show less")
* Other spacing and border fixing.

Change-Id: I956fcec141d12c83261be2710cb971a97b9f7b35