Add docs to repo

[joelfrederico]

This follows the Documenter.jl paradigm for creating docs. Right now, it's bare: only the usage section has been moved from the README.md into the docs. I can continue documenting if this is accepted and there is interest.

[joelfrederico]

Some setup is necessary, see: https://juliadocs.github.io/Documenter.jl/stable/man/hosting/

[stevengj]

Thanks, this looks good.

(The ZMQ.jl package was created before docstrings existed in Julia, much less Documenter.jl.)

[stevengj]

I set up the public/private keys in the Travis and repo settings; does that make this ready to merge?

[joelfrederico]

Almost! You'll also need to create a gh-pages branch for tracking doc history and then point the repo's GitHub.io docs to that branch. And also update the repo's byline with the github.io link.

[stevengj]

The docs you linked says that the branch will be created automatically by deploydocs if needed?

[joelfrederico]

It does say that, when I did that in my fork it didn't happen though and I had to make it manually. YMMV?

[joelfrederico]

Awesome! At some point I may document things as I learn the lib.