just-lock: Support special pragma for plain imports

Marking a source repository 'as plain' means that the whole source
repository tree will get imported as a repository type
corresponding to the source type. In this case, additional pragmas
than those supported by the inndividual imports might need to be
set.

Solve this by supporting the just-mr-style 'pragma' field also in
the source description, for all sources also accepting the
'as plain' field. Currently support only the 'special' pragma.

Document change and add test for plain imports that checks this
feature.

0 files changed, 0 insertions, 0 deletions