Ht evolver calibration

[ezirayw]

What? Why?

Bring in modifications for ht-evolver

Changes proposed in this pull request:

• calibration
• experiment graphing

Checks

• Updated documentation.
• Follows 7 rules of great commit messages. For most PRs a single commit should suffice, in some cases multiple topical commits can be useful. During review it is ok to see tiny commits (e.g. Fix reviewer comments), but right before the code gets merged to master or rc branch, any such commits should be squashed since they are useless to the other developers. Definitely avoid merge commits, use rebase instead.
• Follows the Google Style Guide.

Any screenshots or GIFs?

[zheins]

Hey @ezirayw, you need to rebase this to to the current rc and resolve conflicts.