Add support for sockets

[james-pre]

Sockets are the basis for TTYs and networking. Supporting them would really expand upon the feature-completeness of ZenFS. Also, this is a step towards supporting TTYs, which are used for standard I/O streams.

[cheplv]

@james-pre As "Sockets" you mean: https://en.wikipedia.org/wiki/Unix_domain_socket ?

[james-pre]

@cheplv,

Yup— the goal is to support Node.js' net.Socket API, which will be needed for TTYs and standard I/O streams.

[cheplv]

@james-pre Ok, good. Possible will help with this task in future.