Fix history bug and add bells in analysis.py

[AUdaltsova]

Pull Request

Description

Analysis.py results were inconsistent because run.history() was pulling 500 random steps instead of the whole history. Fixed that.

Bells and whistles:

• Added epoch number to the legend label for easier assessment. May be redundant, happy to remove it

How Has This Been Tested?

Ran analysis.py several times for the same set of runs to make sure it gave consistent results; separately tested that run.lastHistoryStep was working as expected

• [X] Yes

Checklist:

• [X] My code follows OCF's coding style guidelines
• [X] I have performed a self-review of my own code
• [ ] I have made corresponding changes to the documentation
• [ ] I have added tests that prove my fix is effective or that my feature works
• [X] I have checked my code and corrected any misspellings

[AUdaltsova]

@peterdudfield turns out I made the change and never merged, mind taking a quick look when you have a minute?