Updated logic for categories.
First part of predicate logic parser.
Some tweaks in parser
Some functions to apply logic to category.
Updated submodule.
First filenames.
Merge remote-tracking branch 'Sepp/master'

* Sepp/master:
  commit in submodule
Updated submodule.
Merge branch 'master' into logic_parser_devel

* master:
  Updated submodule.
  Updated submodule.
  commit in submodule
Hooks for Predicates and Implications.
Merge remote-tracking branch 'Sepp/master'

* Sepp/master:
  UniversalMorphismFromCoproduct
  UniversalMorphismIntoDirectProduct
IsEqualForObjects

now the set of objects is constructive.