QUNIT2 upgrade

This updates the tests to use QUnit@2.x.x.

#17

named stacks and peakValue

You can now call .start() with a name useful for debugging like:

ObservationRecorder.start("some debug label");

This also exposes a .peekValue() which lets you read an observable without leaking ObservationRecoder.add calls:

var num = value.with(3)

ObservationRecorder.peakValue(num) //-> 3

v1.2.0

Add "use strict" #11

Doc fixes

d110142

v0.2.0

• start returns deps