Re: Turtle tests blank ID patches, and EARL report for Serd

After some more work, Serd now passes all tests except those for the
contested PrEfiX/BaSe syntax (support for these redundant misfeatures is
not planned).

Attached is an updated EARL report.  As before this is against the
trivially patched suite.

My code coverage report suggests the following new areas of the grammar
are not covered:

 * Bad escape in prefix
 * Dots in prefixed names
 * Digits, underscore, dot in blank node labels
 * Error case: dot inside anonymous, e.g "[ :foo :bar :baz. ]"
 
I'll try to submit additional test cases to cover these areas in the
next few days.

Another thing worth mentioning is that I encountered more bugs than the
basic tests expose by doing a round-trip test for those with output,
e.g. read ntriples output, write turtle, read turtle, write ntriples,
compare output ntriples with starting output ntriples from the suite.
This tests that serialization is robust.  Perhaps it would be a good
idea to suggest this for implementations with serialisers in the
definition of rdft:TestTurtleEval?

Cheers,

-dr