Deploy draft PDFs

[drphilmarshall]

This is in response to #39 - let's see whether travis updates the Note in our own doc directory when I submit this pull request...

[drphilmarshall]

Welp, that was a bit of an effort. Draft PDF is now deployed, as in:

https://github.com/DarkEnergyScienceCollaboration/start_paper/tree/drafts/issue/39/deploy_drafts/desc-0000-start_paper-intro.pdf

The scheme is url = $BASEURL/drafts/$BRANCHNAME/$PAPERNAME. I think the branch name has to be in there, because a paper could be being written in multiple branches. You can't go to https://github.com/DarkEnergyScienceCollaboration/start_paper/tree/drafts though: GitHub doesn't enable you to navigate from there.

@kadrlica Thoughts? Feel free to merge it if you like this scheme - or suggest a better way!

[kadrlica]

I have to admit that I'm unfamiliar with this deployment scheme. Is the idea just that this avoids accidentally committing updates to a pdf? In the past, I've always just created a drafts directory where I explicitly copy versioned drafts of the papers that I want to store.

The current scheme makes it a bit hard to find drafts, and it also makes it a bit difficult to understand how to build and publish them. In addition, if you have some special latex tools installed locally, you would need to go into the .travis.yaml to make sure that the pdf would even compile.

My personal feeling is that we are going a bit too far into over-design here. For internal review of documents there will be (i.e., there is already in place for Fermi) a pubboard system where the official drafts of papers are stored. For anyone who wants to browse existing papers/notes, having to go through this convoluted branch structure is not a great way to do it.

[drphilmarshall]

These drafts are really for the people working on them, so they can show the current version as PDF rather than latex. Its useful to pass a link to a readable paper while its being written. Maybe drafts is the wrong word - "currents"? If we don't use the branch name in the URL, then the current/draft version will get over-written by whichever multiple development branches are in play. Maybe that's not a problem in practice - people can always specify their own system, if they want...

It's true that editing .travis.yml files is a bit fiddly. I don't know what to say about that: the easy alternative is that you check in the PDF, but that makes repos get big really quickly. Or, you just look at latex.

[drphilmarshall]

OK, here's the simpler version - dev branches' PDFs get deployed to current, as in:

https://github.com/DarkEnergyScienceCollaboration/start_paper/tree/current