Remove trailing whitespace in files I'm about to edit
Use OR instead of AND when excluding tags for blacklist.

This is because there currently is no way to do this, and this commit doesn't remove the AND capability either.
For example, take the original blacklist "a -b -c".
Currently, that means "Don't show a unless both b and c are present", but now it means "Don't show a unless either b or c are present".
For the original meaning, you now have to do this with two blacklists: "a -b" and "a -c"
Remove useless code
Fix coding style
Support HTTPS in Downloads::File#http_get_streaming
Upload#is_downloadable? returns true for https sources
fix tag api json
add test case for note
moved artist ban to separate action/button
fix artist test
sign out no longer requires http delete, can open up in new window
more robust validation for ip bans
fix ip ban bug
show error messages for user feedback creation
fix similar button for post/show
Merge pull request #584 from 6/https-source

Upload from HTTPS sources
Merge branch 'master' of github.com:r888888888/danbooru
fixes #442
add legacy artist xml api
add legacy artist json api