Missing line was allowing redirects with HEAD

Closes #1203
Unquote proxy usernames and passwords.
Merge pull request #1210 from Lukasa/urlencode_proxy

Unquote proxy usernames and passwords.
Merge pull request #1205 from sigmavirus24/fix1203

Missing line was allowing redirects with HEAD
Revert "If Content-Length is already set.."[1]

This reverts commit 544d08d0f61c35358cf13b4a6b677e4e51dbbe7e.

[1]"If Content-Length is already set, don't over ride it"