cfstream 1.1.1
cfstream 1.1.1: add ocaml version constraint
first opium release 0.3.2
add cohttp dependendy to opium
make a decent description for opium

thanks @Chris00
Merge pull request #1738 from agarwal/cfstream

cfstream 1.1.1
Merge pull request #1742 from mirage/master

cohttp: no need for cstruct dep
Merge pull request #1741 from rgrinberg/master

opium package
cfstream 1.0.0 also depends on ocaml4+