Make sure we load uri module before using it

Here is what happens otherwise: undefined method `URI' for #<Capistrano::Configuration::Namespaces::Namespace:0x007fa9067ac900> (NoMethodError)
Make URI calls compatible with ruby 2.0 (it fails to do a #() call to the module)
Merge pull request #2 from kovyrin/patch-1

Make sure we load uri module before using it