v1.5.13 outsource biom import core to biom package. rm RJSONIO direct dependency
v1.5.13 Fixed namespace issue for extraction methods

Next is to clamp down on Biostrings with some specific importFrom tags
rather than importing the whole bloated package.
Merge pull request #205 from joey711/biom-pkg-depend

v1.5.13 - outsources biom I/O to the biom package. Completes build item 114