Add @aria blade directive (for Accessibility)

[svenbw]

Blade provides a very useful directive @Class to simplify attribute handling for classes.
Adding an @aria directive would improve the readability of the code when a same syntax was available to generate ARIA attributes dynamically.

Changes to support this are rather small;

• Arr::toCssClasses must become an alias of Arr::toTagAttributes (backwards compatibility)
• ComponentTagCompiler::parseComponentTagClassStatements function needs an argument (class and 'aria')

After these 2 changes it should be use possible to use something like aria(['hidden' => $isVisible, 'label' => 'example])