docs(404 errors): provide a better 404 experience

It is a bit rough and ready but does a better job than nothing.
style(jsdoc tags): remove/ammend invalid tags

As highlighted by the new sterner dgeni.
docs(guide/directive): fix typo

`restictions` -> `restrictions`

Closes #6604
docs(guide/migration): fix typos

A few typos fixed.

Closes #6605
docs(guide/migration): fix broken link
docs(ngBind): fix typo

`preferrable` -> `preferable`

Typo fixed

Closes #6606
chore(build): upgrade grunt-jscs-checker to ~0.4.0

this is primarily to resolve peerdependency version mismatch issue
docs($sce): correct typo

`consititute` -> `constitute`

Typo fixed

Closes #6607
docs(changelog): release notes for 1.3.0-beta.1 retractable-eyebrow
chore(release): Update package.json to reflect 1.3.x version
chore(release): update cdn version
docs(Error404): improve search results layout
docs(Error404): better heading
docs(tutorial/step-12): correct application name

Fixed wrong app name:
- phonecat -> phonecatApp, which meets the code in app.js

Closes #6611
docs(guide/providers): remove unneeded word "the"

no need to specify which space, there's only one :)

Closes #6622
feat(): whitelist blob urls for sanitization of data-bound image urls

Closes #4623
docs(guide/forms): remove unnecessary controller reference

the controller reference was breaking the custom validation example

Closes #6525
Closes #6533
docs($route): change routes property to correct type

change $route.routes property type to Object, property is marked incorrectly as an Array

Closes #6552
chore(docs): ensure the "Improve this doc" button is clickable

Closes #6631
docs(ngRepeat): Separate animation class in new lines

Moving to new lines & making it bold to avoid confusion
when they r all in same line without any separation

Closes #6633