Reorganizing ParmEst and Pyomo.DoE Documentation Pages

[slilonfe5]

Fixes # .

Summary/Motivation:

The ParmEst and Pyomo.DoE documentation webpages need a major reorganization ahead of the American Control Conference Workshop in May. This update will enable new/existing users to access recent/forthcoming capabilities in ParmEst and Pyomo.DoE

Changes proposed in this PR:

• Remove outdated/non-informative pages from the ParmEst and Pyomo.DoE documentation webpages
• Update/add documentation files to capture the important features/capabilities in ParmEst and Pyomo.DoE

Legal Acknowledgement

By contributing to this software project, I have read the contribution guide and agree to the following terms and conditions for my contribution:

1. I agree my contributions are submitted under the BSD license.
2. I represent I am authorized to make the contributions and grant the license. If my employer has rights to intellectual property that includes these contributions, I represent that I have received permission to make contributions and grant the required license on behalf of that employer.