Use nicer scrollbars in MS edge

The Mastodon mascot was previously anchored to the bottom, and that was since broken. This restores that behaviour!

It also disables the double-scrollbar behaviour that was caused by this area allowing overflow-y in addition to its parent doing so.

word-break:break-all is a surefire way to break things. It should be set
to normal.
This merge just set it back to what it should be.
Tested on Firefox 52.0.2 and Chrome 56.0.2924.87 with no detected
errors.

Thanks garg

Privacy descriptions were very difficult to reason. This is the minimal level of color contrast to be WCAG AA compliant.

add ability to open status by URL from search (fix #53)

before. In the API, attachments now can be either image, video or gifv. Gifv
is to be treated like images in terms of behaviour, but are videos by file
type.

loaded status; do not preload submitted statuses into community/public
timelines, unless those timelines have already been loaded; do not
close streaming API connections for community/public timelines, once
they have been established (most users navigate back to them eventually)

from zooming in on them