Add check for unsupported platforms

[wweiss]

It would be nice if the install would check for an unsupported platform, like Windows, and gracefully exist if not compatible - similiar to how it is handled with fsevent.

info [email protected]: The platform "linux" is incompatible with this module.
info "[email protected]" is an optional dependency and failed compatibility check. Excluding it from installation.

[missinglink]

This might be easy enough to achieve within package.json, although fsevents seem to have done something different.