Added cookie helpers to halo http request

Signed-off-by: Tom Wright <tom@inflatablecookie.com>
Fixed empty response cookie

Signed-off-by: Tom Wright <tom@inflatablecookie.com>
Added some extra helpers

Signed-off-by: Tom Wright <tom@inflatablecookie.com>
Added http app cookie check for debug var

Signed-off-by: Tom Wright <tom@inflatablecookie.com>