Automatically add ugoira tag to ugoira posts.

Note that this only adds the ugoira tag to .zip posts. It does not
remove the ugoira tag for posts converted from ugoira, but that aren't
true ugoira.
Add tests for filesize: metatag searches.
Don't fudge filesize in filesize:1234b searches.
Add more cases for normalizing pixiv source searches
fixes #2285

Notes need to be disabled because they don't work on webms, the
positions are bugged.

Also enable video controls by default because why not.
Remove rewind button

Not necessary now with the seek slider
#2284 fix aspect ratio with "resize to window"

For some reason the height is getting scaled twice for ugoira, causing a
messed up aspect ratio because it was relative to the current height.
This makes it relative to the original height, so it should always be
correct even after multiple scales.
#2284 resize ugoira controls with image
#2284 hide resize notice
Ensure JSON API returns boolean for Post#has_large.

Currently the JSON API returns null for false and 0 for true for this
attribute. Cast it to a boolean instead.
Include ugoira frames in post data attributes.
Include ugoira data in post JSON API.
Merge pull request #2287 from evazion/fix-has-large

Ensure JSON API returns boolean for Post#has_large.
Merge pull request #2286 from evazion/fix-ugoira-api

Include ugoira data in data attributes and JSON API
Merge pull request #2282 from evazion/feat-autotag-ugoira

Automatically add ugoira tag to ugoira posts.
Merge pull request #2283 from evazion/fix-exact-filesize-search

Fix #2248: filesize metatag: exact match if unit is bytes
Test dupe checking for uploads from Pixiv and FC2.
Don't swallow exceptions from Source::Site.new.

All this method does is call url_match? for each strategy. url_match?
should never throw an exception; if it does there's a bug and it should
be fixed rather than silently ignored.
Simplify source strategy delegation logic.

Instead of having methods check whether the strategy was initialized,
just default to the base strategy when a real strategy isn't available.
Normalize Pixiv URLs for source dupe check.

This ensures these URLs will be detected as duplicates during upload:

* http://i2.pixiv.net/img-original/img/2014/10/18/16/52/44/40456235_p63.jpg
* http://i4.pixiv.net/img-original/img/2014/10/18/16/52/44/40456235_p63.jpg