Add a more intuitive close action for the document viewer

[JustRedTTG]

The current method used for closing the document viewer is to drag from the top (like on the tablet).
Some people find that hard to figure out but cool.
Some people have proposed that other ways of closing the document viewer be added, such as esc or a physical X button

I am leaving this until another way to close the document viewer is implemented.
Leave a thumbs up below or a comment on what you want to see.

[furesoft]

X Button

[JustRedTTG]

Fixed as of eff8f71