docs(ngMock): grammar fix

Small grammar fix for mock $httpBackend documentation.
docs(form.FormController): fix grammar
fix(input): don't dirty model when input event triggered due to placeholder change

Certain versions of IE inexplicably trigger an input event in response to a placeholder
being set.

It is not possible to sniff for this behaviour nicely as the event is not triggered if
the element is not attached to the document, and the event triggers asynchronously so
it is not possible to accomplish this without deferring DOM compilation and slowing down
load times.

Closes #2614
Closes #5960
style(input): fix trailing whitespace

Oops. I blame vim for this little accident.
docs(tutorial/step_12): fix grammar
chore(Scope): name the $watch deregistration function as
chore(jshint): add jshint for the test/ folder
feat(Scope): add `$watchGroup` method for observing a set of expressions

Given an array of expressions, if any one expression changes then the listener function fires
with an arrays of old and new values.

$scope.watchGroup([expression1, expression2, expression3], function(newVals, oldVals) {
 // newVals and oldVals are arrays of values corresponding to expression1..3
 ...
});

Port of angular/angular.dart@a3c31ce1dddb4423faa316cb144568f3fc28b1a9
refactor($interpolate): split .parts into .expressions and .separators

BREAKING CHANGE: the function returned by $interpolate
no longer has a `.parts` array set on it.
It has been replaced by two arrays:
* `.expressions`, an array of the expressions in the
  interpolated text. The expressions are parsed with
  $parse, with an extra layer converting them to strings
  when computed
* `.separators`, an array of strings representing the
  separations between interpolations in the text.
  This array is **always** 1 item longer than the
  `.expressions` array for easy merging with it
perf($compile): watch interpolated expressions individually
refactor($interpolate): attempt to remove hacky code due to $interpolation perf improvements
perf($interpolate): speed up interpolation by recreating watchGroup approach

This change undoes the use of watchGroup by code that uses $interpolate, by
moving the optimizations into the $interpolate itself. While this is not ideal,
it means that we are making the existing api faster rather than require people
to use $interpolate differently in order to benefit from the speed improvements.
docs(guide/forms): fix quotes around updateOn that broke ngModelOptions example
docs(tutorial): update step_11.ngdoc

Change toEqual to toEqualData in the test 'should create "phones" model with 2 phones fetched from xhr'
to make test more consistent.

Closes #7182
docs(tutorial): fix typos in examples

The phonecatApp and phonecatAnimations modules have a dot where a semicolon should be at the end of the sentence

Closes #7167
docs(tutorial/step_03): sync markup with angular-phonecat

Update from Bootstrap 2.3 to 3.1 changed "span" to "col" tags

Closes #7172
docs(tutorial): update step_07.ngdoc

Closes #7169
docs(changelog): release notes for 1.3.0-beta.6 expedient-caffeination
docs(guide/controller): fixed spelling of spiciness

Closes #7185
docs(tutorial/step-12): correct file path

Fixed wrong file path:
- angular/angular-animate.js -> angular-animate/angular-animate.js, which meets the code in app/index.html

Closes #7168