Adding memhub

[mexanick]

Description

Implementing all the necessary changes to incorporate memhub functionality. Changes are transparent for outside users

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Motivation and Context

We need memhub library to ensure the concurrent access to FPGA registers

How Has This Been Tested?

Tested @904 integration test stand with eagle34

Screenshots (if appropriate):

Checklist:

• [x] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [ ] I have added tests to cover my changes.
• [x] All new and existing tests passed.