Rewriting Introduction

[shiffman]

This is my branch where I am rewriting the introduction. I am about half way through at the moment. Here are some notes related to the work:

• Removing "we" as much as possible and using "I" or "you" or "one".
• Changing code references from Processing to p5.js.
• Changing language discussion from Java to JavaScript.
• General edits and clarifications etc. as I notice.
• Filing of issues for things to revisit later.

I will merge this when I complete my pass over the chapter.

It should also be noted that for this to work properly, a commit of the original document as left off in noc-book should be done before any edits are made. See nature-of-code/noc-book-2#24 and nature-of-code/noc-book-2#23 (old version of this pull request).

[shiffman]

😂😂😂

[shiffman]

I changed a lot of whitespace so that diff is not rendering. . . oh well, this one is "ok" for now, I'll be more careful next time or will consider redoing again once I'm finished this pass.

[shiffman]

I've completed this first pass over the introduction. Left to do are:

• format according to Updating README noc-book-2#33
• pool selection Custom distribution of random numbers noc-book-2#142
• perlin noise since 1980 additional context for history of Perlin noise noc-book-2#143

Merging!