Windows support for header-only libraries

[springmeyer]

Currently in mason the only packages which work on windows are header-only libraries. These work on windows because they are only source code and do not need to be pre-compiled by mason.

So, mason does not provide any pre-compiled libraries at this time on windows. This means that mason-js will need to restrict its install support to header-only libraries when it is running on windows.

This work will be needed by mapnik/node-mapnik#834

[millzpaugh]

I'm adding Windows related work for V1 to this ticket, since it's the last outstanding item for creating a test suite #8 - we will also need to create tests on a Windows environment.

[springmeyer]

With node-mapnik dropping windows support (mapnik/node-mapnik#848) this issue is now less of a priority. So, think this can be moved off v1 and we can disable appveyor for now.

[springmeyer]

Closing, as this has not been a need.