#153. Implemented abstract form class and base forms.
#153. Backmerge with master branch.
#153. Added nostrict functional, added get field function, other minor changes.
#153. Changed comparison call and now complex conditions can be created, changed init params, added comments, forms added to the pricing class.
#153. Many errors fixed, added like comparison.
#153.Forms corrected according to the last changes.
#153. Added match validation. ApiKey and MerchantId form changes. Account refactoring.
#153. Removed validators array, cause no need and no used.
#153. Removed underscores from protected vars and methods, minor changes.
#153 Dependency validator added. Ticket #336 fixed.
Merge pull request #395 from laterpay/feature/153_validate_user_inputs

Fixes #153 validate user inputs