support global options (closes Issue 190)
support global options (closes Issue 190)

- new sfepy/base/goptions.py:
  - new ValidatedDict class, goptions instance
  - default_goptions with 'verbose' option

rc/sfepy,sfepy/sfepy,BubuLK/sfepy,lokik/sfepy,sfepy/sfepy,lokik/sfepy,sfepy/sfepy,vlukes/sfepy,RexFuzzle/sfepy,BubuLK/sfepy,vlukes/sfepy,BubuLK/sfepy,RexFuzzle/sfepy,lokik/sfepy,lokik/sfepy,rc/sfepy,RexFuzzle/sfepy,rc/sfepy,vlukes/sfepy,RexFuzzle/sfepy