adding the ability to set a key in consul/etcd through the library
have the configManager encode the value by default
grab the error from encoding if there is one
Merge pull request #8 from ceejh/add-config-set

Add ability to set keys from config package
Updated go sub-repo import path.

See https://groups.google.com/forum/#!topic/golang-nuts/eD8dh3T9yyA for
details.
Merge pull request #9 from jaux/master

Updated go sub-repo import path.