* Update code snippets in README to showcase ray.tune SearchSpaces
- Update definition of parameter distributions to illustrate new
ways of specifying parameter distributions with SearchSpaces.
- Illustrates ways to sample over discrete distributions in a couple of ways

* Updating dependency installs to fix braking tests caused by api changes in dependencies.
- Pinning optimization package versions to match https://github.com/ray-project/ray/blob/master/python/requirements/requirements_tune.txt .
- Adding range of pytest versions in test_requirements

* Update example in README.md, and config for travis

Co-authored-by: mattKretschmer <matthew.kretschmer@gmail.com>

* random-search

Signed-off-by: Richard Liaw <rliaw@berkeley.edu>

* pin

Signed-off-by: Richard Liaw <rliaw@berkeley.edu>

* nobuildiso

Signed-off-by: Richard Liaw <rliaw@berkeley.edu>

* revert

Signed-off-by: Richard Liaw <rliaw@berkeley.edu>

* new-script

Signed-off-by: Richard Liaw <rliaw@berkeley.edu>

* change

Signed-off-by: Richard Liaw <rliaw@berkeley.edu>

* fix

Signed-off-by: Richard Liaw <rliaw@berkeley.edu>

* reduce-files

Signed-off-by: Richard Liaw <rliaw@berkeley.edu>

* Pass estimators via object store IDs

* Bump optuna

* Delete .travis.yml

* Replace references of travis with gh actions

* adding name to run args

* Apply suggestions from code review

Co-authored-by: Rob <rspeare@ip-172-31-8-107.us-east-2.compute.internal>
Co-authored-by: Richard Liaw <rliaw@berkeley.edu>