remove two methods that are never used
move all IO code to io package: helps overview
remove syntax from Readers and Writers. Genericise Syntax on MimeType.
update akka.http from 0.4 to 0.9
fix for issue #156
fix RDFWRiting base for Turtle in Sesame and Plantain. The algorithms for these was just a simple substring calculation, which is not correct.
rename `iso` package to `isomorphism` for clarity ( iso has too many meanings )
rdfxml test  modelled on Turtle. Fix Jena serialiser
Sesame RDFXML relative URI support + dir cleanup
Merge pull request #167 from read-write-web/package_io

move IO classes to their own package, and clean up code