animation-*

[philfreo]

add support for animation-* like these:

.animation-duration(...) {
    -webkit-animation-duration: @arguments;
       -moz-animation-duration: @arguments;
         -o-animation-duration: @arguments;
            animation-duration: @arguments;
}
.animation-fill-mode(...) {
    -webkit-animation-fill-mode: @arguments;
       -moz-animation-fill-mode: @arguments;
         -o-animation-fill-mode: @arguments;
            animation-fill-mode: @arguments;
}

[darcyclarke]

Pull Request?