bugfix to developments:

bugfix to developments:
- if an included .ma file is not found (not in CWD, not in include_paths)
  an error is issued
- if an included .ma file is found but the corrsponding .lexicon is not found
  a development for the .ma is searched:
  - if found it is used to compile the .ma file
  - if not found the user is aked to create a devel for the file included
    (and not the file that he is editing, that may not be in the same devel).