### Please describe the problem.

Trying to add non youtube URL causes an error demanding to set `annex.security.allowed-http-addresses`, which is IMHO not warranted:

[[!format sh """
$> mkdir /tmp/testrepo; cd /tmp/testrepo; git init; git annex init; git annex addurl --file=index.html https://www.cs.toronto.edu/\~kriz/index.html
Initialized empty Git repository in /tmp/testrepo/.git/
init  ok
(recording state in git...)
addurl https://www.cs.toronto.edu/~kriz/index.html 

  This url is supported by youtube-dl, but youtube-dl could potentially access any address, and the configuration of annex.security.allowed-http-addresses does not allow that. Not using youtube-dl.
failed
git-annex: addurl: 1 failed

$> git annex version
git-annex version: 7.20190219+git191-g2d6a364d4-1~ndall+1
build flags: Assistant Webapp Pairing S3(multipartupload)(storageclasses) WebDAV Inotify DBus DesktopNotify TorrentParser MagicMime Feeds Testsuite
dependency versions: aws-0.20 bloomfilter-2.0.1.0 cryptonite-0.25 DAV-1.3.3 feed-1.0.0.0 ghc-8.4.4 http-client-0.5.13.1 persistent-sqlite-2.8.2 torrent-10000.1.1 uuid-1.3.13 yesod-1.6.0
key/value backends: SHA256E SHA256 SHA512E SHA512 SHA224E SHA224 SHA384E SHA384 SHA3_256E SHA3_256 SHA3_512E SHA3_512 SHA3_224E SHA3_224 SHA3_384E SHA3_384 SKEIN256E SKEIN256 SKEIN512E SKEIN512 BLAKE2B256E BLAKE2B256 BLAKE2B512E BLAKE2B512 BLAKE2B160E BLAKE2B160 BLAKE2B224E BLAKE2B224 BLAKE2B384E BLAKE2B384 BLAKE2S256E BLAKE2S256 BLAKE2S160E BLAKE2S160 BLAKE2S224E BLAKE2S224 BLAKE2SP256E BLAKE2SP256 BLAKE2SP224E BLAKE2SP224 SHA1E SHA1 MD5E MD5 WORM URL
remote types: git gcrypt p2p S3 bup directory rsync web bittorrent webdav adb tahoe glacier ddar hook external
operating system: linux x86_64
supported repository versions: 5 7
upgrade supported from repository versions: 0 1 2 3 4 5 6
local repository version: 5
"""]]


The same happens if I remove `youtube-dl` from the system entirely!
[[!meta author=yoh]]
[[!tag projects/repronim]]

> due to using --file which bypasses the usual check that youtube-dl
> can extract media. [[fixed|done]] --[[Joey]]
