promise-A+: separate tested promise from seq points
Merge branch 'promises-aplus-tests-1' of https://github.com/smikes/test262 into promises-aplus-tests-1
A+-README: fix table formatting
A+-harness: document and factor

fold in function setupAllAssertions
early error if `done` is not callable
rename makePromiseTestArray -> makeSequenceArray
document makeSequenceArray
document makeError
A+-README: add documentation

Document completion of async test.
Document assertions system.
Document makeSequenceArray() helper
A+-tests: rename internal variables, seq fn