Propagate error code when test cases are failed

Initial promise tests

packager: make packager runnable

packager.py cannot run due to syntax errors in a few script files

packagerConfig: use git instead of hg
test262: use pop instead of delete to avoid throw if property missing
S22.1.2.1_T*: fix docString header comment: s/b /**
S22.1.2.1_T3: fix docString header comment: s/b /**, fix end of docstring * / => */

doneprintHandle.js: make $DONE accept any falsy argument as meaning 'pass'
PromiseHelper.js: checkSequence: new helper fn for async tests
.gitignore: port .hgignore to .gitignore syntax
test262.py: support $INCLUDE directive in python test runner

S25.4.4.1*: tests to cover Section 25.4.4.1, Promise.all( iterable )
A1.1: Promise.all is callable
A1.2: Promise.all expects 1 argument
A2.1: Promise.all([]) is a Promise
A2.2: Promise.all([]) is resolved immediately
A2.3: Promise.all([]) is resolved with a new empty array
A3.1: Promise.all expects an iterable argument

* mgmeyers/Array.prototype.find:
  Adds tests for Array.prototype.find

* es6Tests:
  first batch of ES6 tests

* hankyates/array-of-tests:
  Adding Array#of tests

* array-from-tests:
  Adding test for Array.from

* tdahlstrom/bug_596:
  Bug 596 - Coverage: 15.4.4.11 - identical elements and array holes

Adding Support for Async Tests

15.5.4.9_CE should check for locale-sensitive comparison

Add contributing.md and update readme.md

change test 15.3.5.4_2-89 to call bound function before returning (Fixes bugzilla 1533)

fix error msgs in test S12.6.1_A1 from Bugzilla issue 1561

change assert to not assume a sorted list of arguments indices (Fixes bugzilla 1159)

fix point of view typos from Bugzilla 1552

fix typo in 10.5 (fixes Bugzilla 1795)

Remove the alert call from test file

Correct shadow behavior in 12.6.4-2 (bugzilla #1450)