Adding luis:init cmd (#401)

* Adding luis:init cmd

* Move save config prompt into init cmd

* Save config settings after creating new app if save flag present

* switching luis prediction endpoint to non-preview

* Removing name flag from luis:version:rename cmd, per specs

* add base level index and LUIS description

* Remove empty options object when no options passed

* Fix index unit test / change query cmd to use slots

* Update radme

* Remove -version flag

* Locking down versions

* Manually updating base readme

* Modifying flag

* Readme commit

* Refactor staging flag

* Fix urls in readme

* Update readme

* Remove dialog cmd, regenerate cli README

* Updating readme

Author: JSpru

README.md

@@ -33,7 +33,6 @@ The following commands are currently available:
 
 #### Future Commands
 The following commands will be ported in upcoming releases:
-* LUIS (API)
 * Dispatch
 
 See [Porting Map](https://github.com/microsoft/botframework-cli/blob/master/PortingMap.md) for a mapping reference between old and new tools