dbtoyaml: fix RuntimeError when using -n option

RuntimeError: dictionary changed size during iteration
Signed-off-by: Philippe Pepiot <phil@philpep.org>
Apply fix for #104 to r0.7 branch.

  dbtoyaml: fix RuntimeError when using -n option
Update AUTHORS for recent pull requests.
Remove 8.4 tests from tox.ini.
Rework split_exprs function in index.py (per DVarrazzo),  Fixes #98.
Merge branch 'r0.7'
Workaround (kludge) to avoid errors in schema UndoSql tests.
Use list of languages in pg_pltemplate in Database._link_refs. Fixes #103.

 * pyrseas/database.py: If running in PG 9.1+, select the list of
   pg_pltemplate languages and pass it to the languages link_refs
   method.
 * pyrseas/dbobject/language.py: Use the list of languages and not just
   plpgsql.
 * tests/dbobject/test_function.py: New test, courtesy of DVarrazzo.
Merge branch 'r0.7'