Trello-69: FEAT: Content updates to FAQs: submission guidance

Content updates to the FAQ static page (/pages/faq), including two new static page additions: /pages/readme, /pages/filetypes. 

Note: commits listed as occurring on 8/29 were cherry-picked from the following commits on 8/27 and 8/28, which had to be re-worked due to an unwieldy re-base against datadryad/dryad-master:

```
git cherry-pick 47a3b7bcef6709e5c2215d013d66072575b452dc
git cherry-pick feb4996bbe0b17a50b43f9e5c27954f918fd6537
git cherry-pick 4851d38a85546660f3bd4a785024efed94e2328b
git cherry-pick 6ff1bd8488133d4752115e4ec9fd2385d60c93f8
git cherry-pick 491f6e4a7b5a4c5a9b2def17c67db24ade870ecc
```

Initial content updates were viewed on dev.datadryad.org. Second-round adjustments, provided by ehull over email, were confirmed on VM build.