docs(dateFilter): properly specify range for the Z format modifier

Closes #1533
feat($compile): '=?' makes '=' binding optional

If you bind using '=' to a non-existant parent property, the compiler
will throw a NON_ASSIGNABLE_MODEL_EXPRESSION exception, which is right
because the model doesn't exist.

This enhancement allow to specify that a binding is optional so it
won't complain if the parent property is not defined. In order to mantain
backward compability, the new behaviour must be specified using '=?' instead
of '='. The local property will be undefined is these cases.

Closes #909
Closes #1435
docs(guide/directives): update obsolete doc reference

Replace an obsolete reference to a nonexistent "Creating Widgets"
section with a real link to "Creating Components".
feat(JQLite): ready() now supports document.readyState=='complete'

JQLite.ready() used for automatic bootstrapping (when jQuery is not present)
now checks if document already is ready when first called. This simplifies
bootstrapping when the angular script is loaded asynchronously.

However if other scripts with angular app code are being loaded as well
it is developers responsibility to ensure that these scripts are loaded
after angular-loader.js is evaluated and before angular.js script is
evaluated.
chore(sortedHtml): print attributes with empty value

I had to also fix some tests as they started failing on IE8.

We should figure out why these extra attributes are set in IE8,
but I'm too tired of IE to worry about it now. Since I'm
not introducing this issue just making it visible, I'm going
to commit this as is.
fix($compile): compile replace directives in external template

Passing DOMNode#childNodes to compileNodes when compiling remote
template, so that directives with replace:true can be compiled.
The previous version used jqLite#contents which returned collection
that was not updated during the compilation.

Closes #1859
fix(ngMock): fix isSpecRunning to work for Mocha

When running inside Mocha, don't look in Jasmine's spec.queue.running.
It's not there. This is documented as issue #1467; I think this issue was
also responsible for #1589 and recent complaints in #1253.

Closes #1467.
docs(ngMock): remove Jasmine-only comments now that Mocha works

Remove comments about angular.mock.inject and angular.mock.module
being available for jasmine only. Since 1.1.1 the intent is that
they be available for mocha as well; now they even work!
docs(ngMock): fix minor typo in comment

Change "constroctor" to "constructor".
fix($http): don't encode URL query substring "null" to "+"

Fixes issue in encodeUriQuery used by $http and $resource that
treats null as a string and replaces the characters "null" with "+".
feat($compile): add attribute binding support via ngAttr*

Sometimes is not desirable to use interpolation on attributes because
the user agent parses them before the interpolation takes place. I.e:

<svg>
  <circle cx="{{cx}}" cy="{{cy}}" r="{{r}}"></circle>
</svg>

The snippet throws three browser errors, one for each attribute.

For some attributes, AngularJS fixes that behaviour introducing special
directives like ng-href or ng-src.

This commit is a more general solution that allows prefixing any
attribute with "ng-attr-", "ng:attr:" or "ng_attr_"  so it will
be set only when the binding is done. The prefix is then removed.

Example usage:

<svg>
  <circle ng-attr-cx="{{cx}}" ng-attr-cy="{{cy}}" ng:attr-r="{{r}}"></circle>
</svg>

Closes #1050
Closes #1925
feat($resource): ability to override url in resource actions

Resources now can defined per action url override. The url is treated
as a template rather than a literal string, so fancy interpolations
are possible.

See attached tests for example usage.
feat($route): add `caseInsensitiveMatch` option for url matching

with this property urls can be matched case-insensitively which
enables some new use cases.
feat($compile): support for dynamic template generation

`template` and `templateUrl` properties can now be optionally defined
via a function. This allows templates to be dynamically generated on
the fly.
feat($compile): allow directives to modify interpolated attributes

A directive can now set/update/remove attribute values even those containing
interpolation during the compile phase and have the new value be picked up
during the compilation.

For example in template:

<div replace-directive some-attr-or-directive="{{originalInterpolationValue}}"></div>

the replace-directive can now replace the value of some-attr-or-directive during compilation
which produces this intermitent template:

<div replace-directive some-attr-or-directive="{{replacedInterpolationValue}}"></div>

or even

<div replace-directive some-attr-or-directive="replacedStaticValue"></div>

as well as

<div replace-directive some-attr-or-directive></div>
chore(Grunt): switch from Rake to Grunt

Migrates the Angular project from Rake to Grunt.

Benefits:
- Drops Ruby dependency
- Lowers barrier to entry for contributions from JavaScript ninjas
- Simplifies the Angular project setup and build process
- Adopts industry-standard tools specific to JavaScript projects
- Support building angular.js on Windows platform (really?!? why?!?)

BREAKING CHANGE: Rake is completely replaced by Grunt. Below are the deprecated Rake tasks and their Grunt equivalents:

rake --> grunt
rake package --> grunt package
rake init --> N/A
rake clean --> grunt clean
rake concat_scenario --> grunt build:scenario
rake concat --> grunt build
rake concat_scenario --> grunt build:scenario
rake minify --> grunt minify
rake version --> grunt write:version
rake docs --> grunt docs
rake webserver --> grunt webserver
rake test --> grunt test
rake test:unit --> grunt test:unit
rake test:<jqlite|jquery|modules|e2e> --> grunt test:<jqlite|jquery|modules|end2end|e2e>
rake test[Firefox+Safari] --> grunt test --browsers Firefox,Safari
rake test[Safari] --> grunt test --browsers Safari
rake autotest --> grunt autotest

NOTES:
* For convenience grunt test:e2e starts a webserver for you, while grunt test:end2end doesn't.
  Use grunt test:end2end if you already have the webserver running.
* Removes duplicate entry for Describe.js in the angularScenario section of angularFiles.js
* Updates docs/src/gen-docs.js to use #done intead of the deprecated #end
* Uses grunt-contrib-connect instead of lib/nodeserver (removed)
* Removes nodeserver.sh, travis now uses grunt webserver
* Built and minified files are identical to Rake's output, with the exception of one less
  character for git revisions (using --short) and a couple minor whitespace differences

Closes #199
docs($http): add more info about transform function
chore(Grunt): don't remove root dir from zip
chore(Grunt): include dot files in the final zip
docs(contribute): add note about running command line as admin on win