- added a way to set raw path to the file in FileFormField - necessary for simulating HTTP requests
- added support for the HTTP PATCH method
- refactored the Form class internals to support multi-dimensional fields (the public API is backward compatible)
- added a way to get parsing errors for Crawler::addHtmlContent() and Crawler::addXmlContent() via libxml functions
- added support for submitting a form without a submit button