fix($httpBackend): Ignore multiple calls to onreadystatechange with readyState=4

On mobile webkit `onreadystatechange` might by called multiple times
with `readyState===4`  caused by xhrs that are resolved while the app is
in the background.

 Fixes #5426.
test(rootScope): reorganize $watch deregistration specs into a describe
fix(Scope): don't let watch deregistration mess up the dirty-checking digest loop

Closes #5525
docs($compile): fix typo

Closes #5599
fix(ngRepeat): allow for more flexible coding style in ngRepeat expression

With this change it's possible to split the ng-repeat expression into multiple
lines at any point in the expression where white-space is expected.

Closes #5537
Closes #5598
fix($browser): remove base href domain when url begins with '//'

This change prevents an incorrect appBase url from being calculated when the
<base> href's domain begins with '//'.

Closes #5606
style($browser): remove ws, fix typo
fix($location): $location.path() behaviour when $locationChangeStart is triggered by the browser

Fixed inconsistency in $location.path() behaviour on the $locationChangeStart event when using
back/forward buttons in the browser or manually changing the url in the address bar.
$location.path() now returns the target url in these cases.

Closes #4989
Closes #5089
Closes #5118
Closes #5580
docs(error/ngRepeat/dupes): fix typo

Closes #5610
fix($httpBackend): use ActiveX XHR when making PATCH requests on IE8

IE8's native XHR doesn't support PATCH requests, but the ActiveX one does.

I'm also removing the noxhr error doc because nobody will ever get that error.

Closes #2518
Closes #5043
fix(httpBackend): fix 'type mismatch' error on IE8 after each request
fix(ngShow/ngHide, ngIf): functions with zero args should be truthy

Previously, expressions that were a function with one or more arguments evaluated to
true, but functions with zero arguments evaluated to false.

This behavior seems both unintentional and undesirable. This patch makes a function
truthy regardless of its number of arguments.

Closes #5414
fix($resource): prevent URL template from collapsing into an empty string

if url template would result in an empty string, we should make a request
to '/' instead.

Closes #5455
Closes #5493
docs(\$sniffer): fix minor typo

Closes #5544
docs($filter): fix wrong param order in doc

fix wrong param order in doc for filter comparator
doc function param for filter expression

Closes #5365
Closes #5611