Jasmine Externs are out of Date

[dgp1130]

I've found that many Closure externs are out of date for Jasmine. Specifically, I see:

• Many custom matcher types are missing, including:
  • CustomMatcherFactories
  • MatchersUtil
  • CustomEqualityTester
  • CustomMatcher
• Jasmine's pretty print utility is missing (jasmine.pp())
• Most matcher functions (toBe(), toEqual(), etc.) accept an optional string to use as an error message if the expectation fails. This is also missing.
• Likely others...

Without these types, custom matchers are basically impossible. Would be great to see these types updated.

See: https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/types/jasmine/index.d.ts

[ChadKillingsworth]

We would happily review a PR that updates these.