Document the possible presence of multiple variables with the

same name in http queries, which might confuse the manager.

Replace calls to ast_uri_decode() with a local function that also
replaces '+' with ' ', as this is the normal encoding for
spaces in http requests.
This allows passing cli commands to the manager through the
http interface.



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@117295 65c4cc65-6c06-0410-ace0-fbb531ad65f3