docs(compile/nodomevents): fix typo ng-mode -> ng-model

correcting directive name to ng-model instead of ng-mode in nodomevents.ngdoc

Correcting use of ng-model directive

Closes #6036
docs($provide): return instance of Ping, rather than constructor

Updating $provide.service method docs

The previous example provided for the service method did not work.  I've updated the example to a working example.

I think this version of the example will probably make more sense to most people, and the factory method would be
a better place for this sort of example.

Closes #6008
chore(grunt): sort the grunt task load statements
chore(build): add jscs code style check to our build

Closes #6062
fix(docs): clarify doc for "args" in $broadcast and $emit

Closes #6047.
Edited the 'Flushing HTTP requests' section

Minor grammatical edits in the Flushing HTTP requests section.
fix(filterFilter): don't interpret dots in predicate object fields as paths

Closes #6005
Closes #6009
chore(travis): remove BrowserStack credentials

Closes #5596
fix($compile): retain CSS classes added in cloneAttachFn on asynchronous directives

Previously, classes added to asynchronous directive elements during the clone
attach function would not persist after the node is merged with the template, prior
to linking. This change corrects this behaviour and brings it in line with synchronous
directives.

Closes #5439
Closes #5617
fix($q): make $q.reject support `finally` and `catch`

Add support for the functions `finally` and `catch` to the
promise returned by `$q.reject`

Closes #6048
Closes #6076
docs(guide/templates.css-styling): fix "`{{}}`"

Replace {{}} to `{{}}` so that "{{}}" is rendered in the HTML page

Closes #5950
fix($http): update httpBackend to use ActiveXObject on IE8 if necessary

window.XMLHttpRequest is not always available in IE8 despite it not running in quirks mode,
in which case Angular should be using the ActiveXObject instead. Just checking the browser
version is taking too many shortcuts.

Closes #5677
Closes #5679
fix(http): make jshint happy
docs(animations): ngClass usage should link to ngClass documentation

Fixing reference to ngClass documentation

Closes #6089
fix(ngResource): don't append number to '$' in url param value when encoding URI

Previously, if a URL parameter value included a $, it would replace the dollar sign with a literal
'$1' for mysterious reasons. Using a function rather than a replacement string circumvents this
behaviour and produces a more expected result.

Closes #6003
Closes #6004
docs(changelog): release notes for 1.2.11
chore(release): cut v1.2.11 release
chore(release): start v1.2.12 (1.2.12)
chore(release): update cdn version
chore(ngClass): remove debugger statement from an e2e test