[Documentation Update Request] Add Linklater to 'Community' section

[cameronj86]

Linklater is a new Android client.

Still in its infancy from the look of things, but personally, the fact that it allows for Android Share instantly makes it more useful than using the Firefox Mobile extension.

[sissbruecker]

Feel free to add it, you can edit the README yourself through the Github UI to open a pull request.