[Question] How do we incorporate systematics?

[aewallwi]

@steven-murray suggests including different classes that add different systematics to the likelihood that includes an API that can be used to create custom systematics models too.

[aewallwi]

In principal, we can add the systematics to our covariance in uvpspec so we don't have to perform explicit modeling?

[aewallwi]

@acliu suggests: lets start by making this class working without doing substantial work on systematics modeling.