Katib v1beta1 documentation update (#2312)

* Rename hyperparameter-tuning to Katib

* Modify overview and hyperparameter

* Modify docs for v1beta1

* Add v1beta1 REST api doc

* Make metrics collector not capitalized

* Add currentOptimalTrial info

* Update UI images

* Change describe to get command

* Add v1alpha3 gRPC API ref

* Add comments to v1alpha3

* Change REST to gRPC

* Add default values for metrics collector

* Change image tag to v1beta1-e294a90

* Changes after review

* Fix list

* Update v1beta1 reference

* Add period

* Add shell to commands

* Fix colon

* Address second review comments

* Changes after doc check

* Fix API links

* Make changes for the trial template

* Modify trial doc

* Apply a11y rules

* Address the comments

* Changes for trial template guide

* Trial template changes

content/en/_redirects

@@ -70,7 +70,7 @@
 docs/started/requirements/                    /docs/started/getting-started/
 
 # Created a new components layout
-/docs/components/hyperparameter                /docs/components/hyperparameter-tuning/hyperparameter
+/docs/components/hyperparameter                /docs/components/katib/overview
 /docs/components/chainer                       /docs/components/training/chainer
 /docs/components/modeldb                       /docs/components/misc/modeldb
 /docs/components/mpi                           /docs/components/training/mpi

content/en/docs/about/use-cases.md

@@ -89,7 +89,7 @@ auditability and compliance requirements.
 
 See these docs for more information on the topics covered above:
 
-- [Hyperparameter tuning with Katib](/docs/components/hyperparameter-tuning/)
+- [Hyperparameter tuning with Katib](/docs/components/katib/)
 - [Training models with operators](/docs/components/training/)
 - [Get started with Pipelines](https://www.kubeflow.org/docs/pipelines/)
 - [Jupyter notebooks](/docs/notebooks/)