added screed and read_parser streaming testing

Marked as known failing since they currently fail.
Will investigate.

Relevant to #393, #654
On Fri, Nov 14, 2014 at 10:44:24AM -0800, bocajnotnef wrote:
> > @@ -1548,3 +1554,166 @@ def test_count_overlap():
> >      assert '178633 1155' in data
> >      assert '496285 2970' in data
> >      assert '752053 238627' in data
> > +
> > +
> > +def execute_streaming_diginorm(ifilename):
> > +    '''Helper function for the matrix of streaming tests
> > +    i.e. uncompressed fasta, gzip fasta, bz2 fasta,
> > +    uncompressed fastq, etc.
> > +    This is not directly executed but is run by the tests themselves'''
> 
> Would ''' also get its own line at the start?

My memory of PEP8 says no, but check.