fix(ngRepeat): correctly iterate over array-like objects

[gonzaloruizdevilla]

Check if the object is array-like to iterate over it like it's done with arrays.

Closes #2546

[petebacondarwin]

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[petebacondarwin]

This is failing on IE8: http://ci.angularjs.org/job/angular.js-pete/122/console

[gonzaloruizdevilla]

$watchCollection needed to use isArrayLike instead of isArray to prevent this error in IE8. I pushed the change with its test in another commit.

I've already signed the CLA as Gonzalo Ruiz de Villa

[petebacondarwin]

Landed at 1d8e11d