Added flowgram (before final check)
Added continued flowgram support.
Finished adding loaders in C (IO)
Working functions and c-IO.  Stripping down read_sff to only handle reads and the flowgrams for QA handling at this point.
Continued flow support
Flowgram support finalized; prior to writing functions to access flowgrams/graphs from data files
Added functions (flowgram() and flowindices() ) to access the respective parts of the flowgram.
merge flow_support with main