Fix comments template and preprocess

The template file in dev contain D6 and attempt at D7 which causes comments to be output twice. Also variables used in template are not set becuase template preprocess function is commented out. I have gone through the code and made it functional maintaining simmilar features and display as in D6 but removed any code that is now provided by core (such as CSS class suggestions).

• Update template file to use D7 rendersing and classes.
• Update preprocess_comment to provide variables needed by template.
• Modify some styles in blueprint.css where class tags have been renamed in D7.