[WIP] Swift reboot

Updating presentation for Swift, and trying to address the feedback in #21. Anything in all caps is a note for myself about something that still needs to be done.

The presentation itself is in [Deckset](decksetapp.com) format now, intended for use with the “Next” theme.

- [Source Markdown](https://github.com/jspahrsummers/enemy-of-the-state/pull/22/files#diff-75)
- [Rendered PDF](https://github.com/jspahrsummers/enemy-of-the-state/raw/reboot/Enemy%20of%20the%20State.pdf) (does not include presenters' notes, and may be a couple revisions behind)

Comments welcome! :heart::bow:

**To do:**

 - [ ] Add code samples where missing
 - [ ] Add presenters' notes where missing
 - [ ] Audit apostrophes and quotation marks
 - [ ] Think hard about ordering
Have you considered using network io as an example here? I could imagine that people start wondering how or if they could write these tests without mocking and stubbing, e.g. by using a in-memory database. With network stuff, there's less of an argument to be had and a code example like

```objc
stubRequest(@"POST", @"http://github.com/signup")
    .withBody(@{ @"username": @"foo", @"pw": @"***" })
    .andReturn(201, userFixture);

expect([client signUpWithUsername:@"foo" password:@"***"]).to.beTruthy();
```

could be easier to parse?