Address Python rdflib parsing issues with examples

[ajnelson-nist]

(This is a re-post of Issue 2 from the prior repository.)

I tried ingesting all of the example files in all of their formats into the CASE Python API, and received some rdflib parsing issues before anything involving the CASE API.

This minimal Bash/Python script loops through the examples/ directory's XML and reports problems there. Here is a truncated shell transcript including the Bash line and the relevant part of the last error encountered:

$ ls *json *ttl *xml | while read x; do python3.5 -c "import rdflib ; rdflib.Graph().parse('$x')" ; done
INFO:rdflib:RDFLib Version: 4.2.2
# [snip]
rdflib.exceptions.ParserError: file:///.../examples/tsk_volume_system.xml:10:4: rdf:nodeID value is not a valid NCName: 51ee2f70-af0f-4ac7-9765-7bf7aa565ddf
$ echo $?
1

All XML files but bz2.xml had a problem. However, bz2.json and bz2.ttl also failed to parse.

This Issue is good to close when that little loop runs without a hitch.

Execution environment: macos Sierra, MacPorts-installed Python and rdflib via py35-rdflib.