[Devel] commands cannot be used in branch_route block

[Juha Heinanen]

i tried to implement branch specific nat traversal and found that the
following commands that i would have needed to call from branch route
block were not allowed:

t_on_reply
add_rr_param
is_method

would it be ok to just add BRANCH_ROUTE to the list of these commands or
would it result to problems?  we already discussed add_rr_param, but if
i remember correctly, problems were related to failure route blocks, not
branch route blocks.

-- juha