The RFB protocol specifies a max version of 3.8, but RealVNC likes to
increment their version when they add new features. RealVNC 5.3 sends
"005.000" as the version string, since they've extended their
implementation upon RFB v3.8. We can detect that, and just tell them we
only speak 3.8, instead of barfing on "005.000" as an invalid version.
This commit moves all the input-related files from `core/`
to `core/input/`, and renames a couple as relevant
(input.js --> input/devices.js, keyboard.js --> input/util.js).
This commit restructures noVNC, splitting it into the core directory
and the app directory, with the former containing core noVNC parts,
and the latter containing parts specific to the application.