The s:RegistrationCommands functions will now test the type of the "specs" rpc call. If it's not a list, then the plugin failed to load and is skipped
Issue: #1537 Running the :UpdateRemotePlugins command will show an ugly, unhelpful error when no plugins were found. This change has neovim print an error message and does not attempt to start the python-client which requires at least one plugin.
- Rename autoload/rpc to autoload/remote - External plugins are now remote plugins - External plugins directory is "rplugin"