mastodon search api: implement a reasonable hashtags stub

See merge request !89

config: make the upload limit configurable

See merge request !88

Bring Mastodon frontend up-to-date

See merge request !87

collections.

Should speed up the queries because ecto doesn't have to parse the json.

with my fork of it, @ https://git.pleroma.social/howl/mastofe .

Add char_limit to initial-state of mastofe

See merge request pleroma/pleroma!86

object carry their emoji information.