Teach read.amiramesh to handle gzipped files (via R.utils) and reinstate test
Merge branch 'read.amiramesh_gzip' of github.com:ajdm/nat into ajdm-read.amiramesh_gzip

* 'read.amiramesh_gzip' of github.com:ajdm/nat:
  Teach read.amiramesh to handle gzipped files (via R.utils) and reinstate test
implement and test is.gzip()

* NB this is a private function in nat for now
* propose to add to nat.utils soon
Switch to nat:::is.gzip to avoid R.utils dependency

* note that use of gzfile is essential to fix #14
Merge branch 'ajdm-read.amiramesh_gzip'

* ajdm-read.amiramesh_gzip:
  Switch to nat:::is.gzip to avoid R.utils dependency
  implement and test is.gzip()
  Teach read.amiramesh to handle gzipped files (via R.utils) and reinstate test