added data dumper util in order to debug globaleaks data structures
First stab at defining the data structure of fields
Upgrade requirement `cryptography` to 0.5.
Add steps table.
Merge branch 'feature/fields_refactor' of github.com:globaleaks/GLBackend into feature/field_refactor
First stab at SQL schema definition
fixed a little bug on reference
Write first passing unittest.
started UT, fixed conflict
sequence to create Field and FieldGroup
Fix some unittests.
Merge remote-tracking branch 'origin/feature/fields_refactor' into feature/fields_refactor

* origin/feature/fields_refactor:
  sequence to create Field and FieldGroup
  started UT, fixed conflict

Conflicts:
	globaleaks/db/sqlite.sql
	globaleaks/models.py
Merge branch 'feature/fields_refactor' of github.com:globaleaks/GLBackend into feature/field_refactor
Refactoring of unittests for field and fieldgroups
Review and integrate one-to-many relationship between fields and fieldgroups.

To each field correspond a single fieldgroup, and fieldgroups might be collected
in other fieldgroups.
Merge remote-tracking branch 'origin/feature/fields_refactor' into feature/field_refactor

Conflicts:
	globaleaks/models.py
	globaleaks/tests/test_models.py
Add specification for ng-fields
Fixing fields and fieldgroup relations and writing tests.
Merge remote-tracking branch 'origin/feature/field_refactor' into feature/fields_refactor
fixed various bugs in tests for fields