Modified version of the CSV Conversion spec.
Added a TBD class to the template part
Reorganized the text to fall back on a 'virtual' metadata for the Core Data Model case
Fix IRI escape in example. Add some example comments.
More missed entity escapes. Also, set default prefix to base + "#"
Merge commit 'd58d573df11ece9fb29b1781ed146747e92ce2af' into rdfconversion-ivan