refactor: utils should have a function to get all prefixed attributes

[devversion]

We need a util method, which returns all prefixed attributes.

#getPrefixedAttributes

$mdUtil.getPrefixedAttributes('ng-click');
// Returns ['ng-click', 'data-ng-click', 'x-ng-click']

#hasPrefixedAttribute

var el = angular.element('<div data-ng-click="null">');

$mdUtil.hasPrefixedAttribute(el, 'ng-click');
// Returns true;

#getPrefixedAttributeSelector

$mdUtil.getPrefixedAttributeSelector(['ng-click', 'ng-mouseenter']);
// Returns [ng-click], [data-ng-click], [x-ng-click], [ng-mouseenter], 
// [data-ng-mouseenter], [x-ng-mouseenter]

• We query really often for elements with attributes (but not with prefixed)
• We often copy attributes to another element and need to specify the prefixed attributes manually.
• Sometimes we want to know if an element has an attribute (even with prefixed attrs)

We repeat the same code really often for different components, like list, menu etc.

• feat(menu): check for ngClick and ngMouseenter data attributes #7568