Add new aggregate report tiers "ProbAA" and "RefMatch"

[susannasiebert]

We've been prototyping incorporating reference matches and problematic amino acid inclusion in our pipelines for the last few months. Currently, these criteria are used to prioritize neoantigen candidates when selecting the Best Peptide but are not formally included in the tiers. We want to add two new tiers "ProbAA" and "RefMatch" as follows:

• For a candidate to be considered "Pass" there can be no problematic amino acid positions and RefMatch has to be False
• These criteria would count towards a candidate being Poor and would be highlighted as problematic in the the pVACview interface
• If a candidate meets every other criteria but has any problematic amino acid positions it would get tiered as: ProbAA
• If a candidate meets every other criteria but has a Reference Match, it would get tiered as: RefMatch

As part of this PR, we need to revisit the sorting of these criteria for the default sorting in the aggregate report as well as the coloring of the tiers in pVACview.

[susannasiebert]

Malachi suggested the following:

I wonder if a simpler scheme would be fine:

• Pass = Green
• Tiers indicating one specific issue = Yellow
• Poor = Orange

[susannasiebert]

We also decided to add a third new tier "Binding" that denotes that just the binding criteria was failed. As a result, all neoantigen candidates in the Poor tier fail two or more candidates, which is more consistent and intuitive than the previous behavior.