doc(angular.forEach): note difference from ES262's Array.prototype.forEach

Since Angular's forEach is not a strict polyfill, and takes different paths depending on the type
of collection it is dealing with, it does not throw a TypeError when converting the obj with
ToObject(), as this operation does not need to be performed.

This difference is documented nicely here.

Closes #9142
docs(input): `ngModel` uses priority 1
docs(guide/directive): fix typo
refactor($compile): simplify regular expressions

Closes #9637
refactor(jqLite): remove a duplicate DOMContentLoaded handler attachment
docs(jqLite): typo: `getComputedStyles()` -> `getComputedStyle()`
docs(ngEventDirs): update remarks on behavior

The event directives haven't stopped propagation by default in a long time.
If that behavior is desired, the handler may use the provided `$event` to call:

    $event.stopPropagation();

Closes #9640
docs(guide/forms): improve readability and formatting
fix(loader): fix double spaces

Fix double spaces in return statement. Double spaces between return and
returned value brake minification process of some minifiers (bug found on JSMin
https://github.com/mrclay/jsmin-php).

Closes #9630
test($resource): enhance test-case to verify correct behaviour

Previously, the test-case verified that calling `toJson()`, would remove
the `$promise` and `$resolved`, but not that other `$`-prefixed properties
would not be removed.

Closes #9628
docs($location) fix $$parse parameter name

Replaced newAbsoluteUrl by url parameter.

Closes #9650
chore(jscs): update jscs and update deprecated rules

Updated grunt-jscs and deprecated rules:
requireLeftStickedOperators and requireRightStickedOperators.

Fixes #9429
Closes #9616
chore(jscs) change deprecated rules for jscs todo

Closes #9616
docs(readme): fixing the &lt; in the benchmarks readme.md page

Closes #9615
docs(ngModel): clarify usage of formatters / parsers and $setValidity
docs(guide/forms, ngModel): update list of css classes
docs(input): clarify input and ngModel behavior
docs(guide/forms): update custom validation section with $validators
docs(guide/forms, input): add information how to modify built-in validators

Closes #5757
Closes #7798
docs(guide/form): shorten line lengths for better readability