Closes #9989

Closes #8605

Also add tf_prompt_info to the list of prompt functions so theme writers are aware of it

In the home directory there is a .terraform folder for modules but it is most likely not
an actual directory of terraform scripts. Therefore, this patch disables checking for workspace in the home directory.

* Fix the terraform function name

Current function name do worse. I always use `terr<TAB>` and before those prompt it was add space in the end. Now because we have multiple functions and binaries started with terraform there are no space.

* Updated terraform readme

Updated the name of new function name

Expanded Terraform plugin with function that can be used to show workspace name in the zsh prompt