Merge pull request #21 from sarahkemp/development

Fix 'required' checkbox
Some updates for Symphony 2.4
Support for multiple DTG fields in one section
Whitespace, fix custom Selects
Section Schemas compatibility...(basic, not with appendFieldSchema)
Add Importable/Exportable Field support
Merge pull request #22 from brendo/development

Updates for Symphony 2.4 (perhaps earlier?)
Merge pull request #1 from brockpetrie/development

updates from parent