Fixes for Concrete5 5.6.1, some tweaks and fixes for W3C validation

0.7.3 - (21 march 2013)
- Fixed controller of block and package to working with attributes for Concrete5 v. 5.6.1 and higher (now checks via is_object instead of boolean).
- Fixed formatTitle for Zoom Mode (now don't shows blank white line if Image Caption is empty).
- Moved CSS to header.
- Some tweaks for W3C validation