Fixed test result graph rendering and added three new dashboard columns

[japod]

This PR addresses issues caused by various NPEs coming from trend graph rendering logic that i experienced while using TAP plugin in our local deployment for NPM package testing.

The PR also introduces several dashboard view columns that help with propagating test counter related information to the view and also help with determining compliance of selected jobs with given "golden" scenario based on test counter values.

Attaching several screenshots to illustrate the functionality added:

Config page of the view named "test":

Golden, base line, project in a view:

Test project "initial", incompatible, state:

Corresponding dashboard view:

Test project stabilized:

Test project, clean run:

Test project back to compatible state:

[kinow]

Looking good, I just need to confirm how to add the dashboard dependency optionally, or if that's not possible if that wouldn't cause issues (with security, updating Jenkins, etc.). In Active Choices Scriptler is an optional dependency, but I think I had to protect against nulls at least when the plug-in was not installed...

Thanks for the PR, sorry for the long delay.

[kinow]

The protection against NPEs looks easy to be reviewed and merged. This dependency and the classes added are a bit more complicated to review, I think. Would be easier if this could be an optional dependency, but I am not sure if that wouldn't cause some runtime errors for users without he plug-in (I think in active choices I have an optional dependency, will check what steps were taken for that.