Enable tapping by default

[Mustafa Muhammad]

Hi, I am testing Fedora 21 beta and -like all previous versions- click
by tapping is off by default.
Several bug reports concerning this were closed as NOTABUG, but
tapping is useful for us (people who use it), I don't think it bothers
the others that much, and is on by default in most operating systems
and Linux distributions.

What can we do to make this happen?

Regards
Mustafa Muhammad