Add leveldb 1.0.3.
Fix leveldb.1.0.3 link issue regarding snappy.
Merge pull request #1700 from mfp/master

Add leveldb 1.0.3.
Relax/fix uint version restriction

The ospec 0.3.0 package can not be installed which in turn blocked uint 1.1.1.

This caused/causes opam to try to install uint 1.0.2 which doesn't work on OCaml 4.x.
Merge pull request #1702 from hcarty/patch-1

Relax/fix uint version restriction
Merge pull request #1701 from hcarty/master

Update zmq and lwt-zmq
+cstruct.1.1.0
cstruct: +ounit dep
Merge pull request #1703 from mirage/master

+cstruct.1.1.0