Submit extension to the Chrome Webstore/AMO

[koma-cute]

Probably after #8

[Difegue]

I hadn't really planned on going through with AMO/webstore submissions since the review processes seem to be quite lengthy.
I do already have an AMO account since the .xpi has to go through it for signing before it ends up in the GH releases here, but it's not set to be published in the store.

Looking at the history for Hydrus Companion kinda turned me off as well, google randomly stopping to accept your updates is not a very good mood.