update MED file support, fix this issue: https://groups.google.com/forum/#!msg/sfepy-devel/z1e83Xgl1_U/884jDfKzKPsJ
update Viewer.call_mlab(): do not show GUI if show option is False
migrate tutorial "Using Salome with SfePy" from google site, see #171
Merge pull request #274 from vlukes/doc_examples
remove long syntax from the user's guide
new doc page with long syntax
tutorial with short syntax of keywords, closes #272