Remove KerasCV and KerasNLP; new structure for KerasHub and KerasTuner (

#1993)

* Updates scripts for new strcuture

* Remove old guides

* Rework templates for new structure

* Add a ton of redirects

* Improve KerasHub doc content

* Improve CV redirects

.gitignore

@@ -11,7 +11,8 @@ templates/examples/rl/*
 templates/examples/keras_recipes/*
 templates/examples/timeseries/*
 templates/examples/graph/*
-templates/guides/**/*.md
-templates/keras-tuner/getting_started.md
+templates/**/guides/**/*.md
+templates/keras_hub/getting_started.md
+templates/keras_tuner/getting_started.md
 datasets/*
 .vscode/*