This change allows us to create manual key maps in the future, allowing
users with different keyboard layoutss to share a profile without having
to rewrite it for their keyboard layout.
Previously, x52d had conditional compilation flags linking to libevdev
on Linux. However, I wanted to change this so that we use an abstraction
layer that will link to the appropriate backend (evdev on Linux only for
now). The idea is that we get rid of all conditional compilation blocks
and deal with the backend through the vkm library.
This new library handles the mouse scrolling, clicking, as well as
adding the ability to include keyboard events so that we can support the
profiles feature in a future commit.