Merge pull request #49 from pyeremenko/master

add long polling support
[maven-release-plugin] prepare release ironmq-0.0.19
[maven-release-plugin] prepare for next development iteration
changing version in readme
Enables a `pathPrefix` option in Cloud for special hosts.
Initialized pathPrefix.
Added full string URL option for Cloud.
slightly change Cloud class
remove trailing slash
small fix
Merge pull request #53 from iron-io/path-prefix

Enables a `pathPrefix` option in Cloud for special hosts.
add deleteMessages overload