Add real docs

[pdeffebach]

This is a major PR (it felt like the last one was, too!)

I am getting us set up with "real" documentation.

1. Transferred the README to index.md
2. Added an api.md with the @doc macros
3. Fixed all the jldoctests so they run

I still need to

1. Write a new README
2. Figure out how to get set up so it's a website

Also, I can't get the link to the api page to work from the index page. If anyone knows how to fix this, please let me know!

cc @bkamins, @nalimilan

[bkamins]

Great! Let me know when you are done and I will have a look (though @nalimilan is much better than me with documentation).

[pdeffebach]

Okay I've taken this PR as far as I'm comfortable with for now.

The changes to the docs are minimal. But lots of examples have been changed to no longer rely on random number generation.

Next step is hosting. If this were my own package I would fumble through the hosting configuration on my own. But given this is owned by JuliaData I would like someone, probably @quinnj or @nalimilan to help take this over the finish line. in particular, the part about adding an ssh key (which I have, I think) and making sure a website actually exists confuses me.

Thank you!

[quinnj]

Usually it's not too bad to setup; I just follow the Documenter.jl guide for hosting; in travis, you put the DOCUMENTER_KEY as an environment variable (I can do this if you dm me the key), then make sure your travis job has a docs build job.

[pdeffebach]

@quinnj or @nalimilan

I've worked through the documenter docs on hosting, and i need to add a ssh key for the repository. I don't have ownership permissions to do that for DataFramesMeta (can't click on settings at the repo page on github). I need one of you to work through this section to set up the SSH deploy keys.

[pdeffebach]

Okay I think this is ready for another review. I have

• Added the ssh key to the Travis settings
• Added the ssh key to the DataFramesMeta settings
• Added the deployment ssh command to the tagbot yml
• Deleted an extraneous appveyer badge
• Added badges for the documentation
• Written a little more on the README

I think that if we merge this the docs should deploy correctly.

Please let me know!

[pdeffebach]

Tests pass!

[bkamins]

is this comparison or an example how one could write ones own extension?

[pdeffebach]

I don't think I want to expose this API formally yet. Its untested, and I don't know if there is a need to someone to write their own extension. I think we should cut this.

[bkamins]

OK - then I would cut this.

[bkamins]

Looks good. Thank you. I have left some minor comments.

[pdeffebach]

Thanks!

I deleted the example about extending @linq but am keeping other piping. @linq isn't perfect so users might want to know about other options.

Ready to merge if people approve!

[pdeffebach]

Thanks for your feedback, everyone! I am going to merge!