Split requests made by Danbooru::Http into either internal or external
requests. Internal requests are API calls to internal services run by
Danbooru. External requests are requests to external websites, for
example fetching sources or downloading files. External requests may use
a HTTP proxy if one is configured. Internal requests don't.
Fixes a few source extractors not using the HTTP proxy for certain API calls.
that's the latest commit made to deviantart files before switching from
the developer API to the Javascript backend from the new "Eclipse"
frontend.
This is necessary because it's basically impossible to download posts
now with the JS backend without being logged in, i.e. having the cookies
from a logged in user, which can't be used for very long even if
exporting them from a browser. You would have to save the cookies
deviantart sends you back via the "Set-Cookie" header in a database
somewhere in addition to the other added complexity.
also
* (temporarily) replace HttpartyCache with HTTParty as it's long been
removed
* fix one case of "last argument as keyword parameter"
* change repository url (5d1a1cc87e)
* remove self-explanatory comment
