Remove configurable run/work dir from global config

[MetRonnie]

These changes close #4034

Remove from global.cylc:

• [platforms][<platform name>]run directory
• [platforms][<platform name>]work directory
• [platforms][<platform name>]suite definition directory

Also remove obsolete --template option from cylc suite-state

Requirements check-list

• I have read CONTRIBUTING.md and added my name as a Code Contributor.
• Contains logically grouped changes (else tidy your branch by rebase).
• Does not contain off-topic changes (use other PRs for other changes).
• Does not need tests (no need to test removed stuff)
• Appropriate change log entry included.
• (master branch) I have opened a documentation PR at Remove configurable work dir from global config cylc-doc#239.
• No dependency changes.

---

• Check these are given deprecation notations in the docs:

  (Note that we also need to deprecate the environment variables $CYLC_SUITE_DEF_PATH & $CYLC_SUITE_DEF_PATH_ON_SUITE_HOST.)

[MetRonnie]

Not sure if there's any test cases I should implement?

[hjoliver]

Not sure if there's any test cases I should implement?

Presumably sufficient to remove any code associated with the obsolete config items, and adapt or remove tests that use it.

[wxtim]

• Tests pass locally.
• Changes look sensible.

[MetRonnie]

Check these are given deprecation notations in the docs:

(Note that we also need to deprecate the environment variables $CYLC_SUITE_DEF_PATH & $CYLC_SUITE_DEF_PATH_ON_SUITE_HOST.)

@dpmatthews I think you brought this up - I can't find any reference to them in the docs at all, so is this point resolved, or should I add something somwhere?

[dpmatthews]

@dpmatthews I think you brought this up - I can't find any reference to them in the docs at all, so is this point resolved, or should I add something somwhere?

We don't appear to document other deprecated env variables so I think that's fine

[hjoliver]

Merge unit test conflict resolution, and confirmed that the result passed.