- Added a common header that includes all public header files.  The pod can then be included via: #include <BPForms.h>.
- Changed BPFormViewController's allCellsAreValid method to only return YES if all cell.validateState == BPFormValidationStateValid.
- Changed BPFormCell's default validationState = BPFormValidationStateValid (BPFormInputCell::setupCell already overrides this value to BPFormValidationStateNone so that any input-style cell is automatically set to be invalid).