bundle2: disable ouput capture unless we use http (issue4613 issue4615) The current bundle2 processing was capturing all output. This is nice as it provide better meta data about what output what, but this was changing two things: 1) adding a prefix "remote: " to "other" output during local push (issue4613) 2) local and ssh push does not provide real time output anymore (issue4615) As we are unsure about what form should be used in (1) and how to solve (2) we disable output capture in this two cases. Output capture can be forced using an experimental option.