SSL peer verification was silently enabled by the HTTParty upgrade in
8a54fda4. This patch restores the
previous behaviour of GitLab 6.3 and earlier.

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

When using web hook with credentials secured web resource, one needs to
put the credentials in the hook URL.

If the credentials contain special symbols (e.g. @ or #), it should be
URL-quoted (e.g. %40 instead of @).

But when Gitlab is making a request, it should unquote the symbols
before base64-encoding them.

A new queue of "project_web_hook" is used to process web hooks asynchronously, allowing each to succeed/fail (and be retried) independently.

(Basically, project web hooks now process the same as system hooks.)

This commit includes:

 * Projects can have zero or more WebHooks.
 * The PostReceive job will ask a project to execute any web hooks defined for that project.
 * WebHook has a URL, we post Github-compatible JSON to that URL.
 * Failure to execute a WebHook will be silently ignored.