replace EMS with AvailabilityManagerOptimumStart

[eringold]

Pull request overview

Replace the EMS implementation of optimum start AHU control with AvailabilityManager:OptimumStart

• Fixes Remove/replace EMS implementation of optimum start Air Loop control #1630

Pull Request Author

• Method changes or additions
• All new and existing tests passes

Review Checklist

This will not be exhaustively relevant to every PR.

• Perform a code review on GitHub
• All related changes have been implemented: method additions, changes, tests
• Check rubocop errors
• Check yard doc errors
• If fixing a defect, verify by running develop branch and reproducing defect, then running PR and reproducing fix
• If a new feature, test the new feature and try creative ways to break it
• CI status: all green or justified

[eringold]

The majority of test failures are from object differences ("A OS:EnergyManagementSystem:ProgramCallingManager was found only in the before model", "A OS:AvailabilityManager:OptimumStart was found only in the after model") which are expected given this change.

The performance test energy diff failures for SecondarySchool-90.1-2016-ASHRAE 169-2013-4A were investigated. The following differences were found in an annual run:

	Energy % Diff	Demand % Diff
Heating	5.7	-1.8
Cooling	0.08	-0.18
Fans	3.96	-0.28
Pumps	3.63	1.61
Total Elec	0.71	-0.12
Total Gas	1.4	-1.17

The overall HVAC system runtime increased by 2.4% with the modification, along with a slight drop in unmet cooling hours (250 -> 247). GIven the uncertainty in the modeled Availability Manager inputs for optimum start (as well as the original EMS implementation) I think these diffs are reasonable.