ENYO-60: Onyx button elements no longer have a forced line-height.

This corrects an issue regarding onyx applying presumptuous rules to all child button elements, which interferes with other libraries.

Enyo-DCO-1.1-Signed-off-by: Blake Stephens <blake.stephens@lge.com>
It didn't seem wise, since we may not have insight into how these label and input elements are used in apps. This change could have very poor layout implications.