consider yaml config implementation

[whilei]

Considering something like...

pkgtests:
  - pkg: "github.com/ETCDEVTeam/go-schroedinger..."
    rerun:
      anyFailing: false
      onlyFailing:
      - name: "TestCat"
        trialsAllowed: 23
      -

Pros:

• allow only "whilelisted" tests to be rerun in case of failure
• extensible and customizable configurations per registered nondeterministic test
• option for explicit listing of nondeterministic tests

Cons:

• adds a significant layer of complexity to configuration decisions... is this level of customization and detail really necessary?

Questions:

• would this co-exist w/ existing simple plain-text file implementation?