babel: noweb insertions are now placed behind the line prefix of the <<>> reference

babel: noweb insertions are now placed behind the line prefix of the <<>> reference

  So, for example since the following <<example>> noweb reference
  appears behind the SQL comment syntax the entire inserted body will
  also be SQL commented

-- <<example>>

  expands to

-- this is the
-- multi-line body of example

  Note that noweb replacement text which does *not* contain any
  newlines will not be affected by this change, so it is still
  possible to use inline noweb references.

  Thanks to Sébastien Vauban for this idea.