Including more information in Collection rndrngs

Including full categories when rendering to text/occi.
This change does NOT break compatibility! Now the text/occi
content pretty much matches the text/plain content
(information-wise).
Including titles when rndrng entities & mixins

This change does NOT break compatibility!
Smarter logging from the OCCI text parser (quotes)
Fixed header handling in Occi::Parser

Sometimes header values get to the parser as single-value arrays.
These have to be normalized by picking the first element and dropping
the rest (ideally nothing gets dropped, but ...).
Updated specs (parser & rendering changes)

Changes in specs to accommodate recent rendering and parsing
changes in Occi::Core and Occi::Parser.
Merge pull request #2 from arax/parser_fix

Parsing & rendering fixes