indexer for RDF data
git ignores for generated sources and exe
fix error on cli args for test_query
add RDF prefixed output for at least the built-in vocabularies

this is hacked together on URIs because for some reason
Raptor doesn't give you the prefixes on a Reader. I would
like to get the prefixes from a Reader to apply directly to the Writer
disable sp2bench that are not supported by compiler

Two main problems
Joins with $0 != $1
condition flip (see issue #104)
add manually expanded RDF strings to sp2b
add manually expanded RDF strings to sp2b
change grappa padding to GRAPPA_BLOCK_ALIGNED
Merge branch 'bmyerz-sp2bench-c' of github.com:uwescience/datalogcompiler into bmyerz-sp2bench-c

Conflicts:
	examples/sp2bench/sp2bench_rdf.py
sp2b for grappa
disable the remove project rule in favor of GrappaProject
cleanup strings2ints, print indices for human readability
Merge branch 'bmyerz-sp2bench-c' of github.com:uwescience/datalogcompiler into bmyerz-sp2bench-c
antijoin comment
case conversion

Signed-off-by: Daniel Halperin <dhalperi@cs.washington.edu>
ignore some generated data files for clang tests
StringIndex: c queries support for indexed strings
string index file: for machine and more readable
copy of sp2bench queries with expanded rdf prefixes
string lookup support in clang

string lookup occurs once per string in the query.
It brings up the need for a new category of clang
emitted code: initials, which happen before the
query execution even begins and should not be in a pipeline
because we don't want them to keep executing.