Feature: use any23 for RDF retrieval

It would be nice to be able to use rover feature of the any23 libray instead of curl. This would allow rdf.sh to work with microdata/RDFa too.

For example:

$ any23 rover -t -f turtle http://schema.org/Event
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option PermSize=128m; support was removed in 8.0
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.

------------------------------------------------------------------------
Apache Any23 :: rover
------------------------------------------------------------------------

[Fatal Error] :133:71: The entity "nbsp" was referenced, but not declared.
@prefix dcterms: <http://purl.org/dc/terms/> .

<http://schema.org/Event> dcterms:title "Event - schema.org"@en ;
    <http://www.w3.org/ns/rdfa#usesVocabulary> <http://schema.org/> ;
    a <http://www.w3.org/2000/01/rdf-schema#Class> ;
    <http://www.w3.org/2002/07/owl#equivalentClass> <http://purl.org/dc/dcmitype/Event> ;
    <http://www.w3.org/2000/01/rdf-schema#label> "Event"@en ;
    <http://www.w3.org/2000/01/rdf-schema#comment> "An event happening at a certain time and location, such as a concert, lecture, or festival. Ticketing information may be added via the 'offers' property. Repeated events may be structured as separate Event objects."@en ;
    <http://www.w3.org/2000/01/rdf-schema#subClassOf> <http://schema.org/Event> .

<http://schema.org/attendee> a <http://www.w3.org/2000/01/rdf-schema#Property> ;
    <http://www.w3.org/2000/01/rdf-schema#label> "attendee"@en ;
    <http://schema.org/rangeIncludes> <http://schema.org/Organization> .

------------------------------------------------------------------------
Apache Any23 SUCCESS
Total time: 1s
Finished at: Thu Jan 29 14:23:45 CET 2015
Final Memory: 65M/479M
------------------------------------------------------------------------

$ rdf desc http://schema.org/Event
rapper: Error - URI http://schema.org/Event - Failed to guess parser from content type '(none)'
rapper: Failed to parse file <stdin> guess content
roqet: invalid output result format `ntriples' for `--results'
Try 'roqet -h' for a list of valid formats
Try `roqet --help' for more information.
grep: repetition-operator operand invalid
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

seebi / rdf.sh

Feature: use any23 for RDF retrieval #8