Incorporate Batch 1 edits into website

Since edits have been approved for Batch 1 content ( #328 ), we are ready to implement on the website.

Steps:

- Under the main nav "About", create two menu options, "Why OpenACR" and "About this initiative"
- "Why OpenACR" content is on [this page](https://docs.google.com/document/d/1SLYSkw7_LjranxhfQgIT6Ksfa6Ns2hKAnphoVEDuUco/edit#)
- "About this initiative" content is on [this page](https://docs.google.com/document/d/1Gxss6UtNsDH-xaH1mUvQpkLKxzjNQdvvzW8bJ3StTxk/edit#)

The rest of the current menu options under "About" should be unpublished. Most of the content has been captured in the re-writing of the two pages above. The rest will be re-written and re-published in the next content batch.