Feature chalk docs

[Meiguro]

The long awaited documentation for all the new features. All the newly introduced color fields are documented, new elements Line and Radial, and new modules Platform and Feature. Two guides are added in order to give a clearer direction for developing on Pebble.js in light of supporting Chalk.

Once everything looks good, a CloudPebble update will be requested, and this will be merged. This will address #96, #116, #156 .

[cat-haines]

should be #using-feature, #feature-vs-platform is defined below

[cat-haines]

link

[cat-haines]

You seem to use links inconsistently in your section headers (I marked a bunch, not all) - not certain if intentional or not...

[Meiguro]

Yes, intentional, the links are only defined if they are necessary. When the header has no strange symbols in it no anchor tag is necessary and it automatically works, but for some odd reason when there are parens or square brackets it's necessary to define your own, or possibly I've not figured out the escape sequence.

[Meiguro]

Thanks for the quick look over! I updated the docs per the comments. I want to eventually add anchors for all headers, but I'm unsure if that's the right way to use Flatdoc at the moment. When I figure out more, I'll fix them all up.

One of my main concerns is if I ordered the guides correctly. I kept Using Images and Using Fonts first since they're short. The two new guides are much longer, but I put the one that most users would find more immediately useful first, which I assume is Using Color. The one gotcha is that it uses Feature before they even read the Feature Detection guide, so I was unsure about that order. Maybe that makes sense since it just subtly introduces Feature.color and Feature.round in the examples, and they can read Feature Detection if they want a fuller understanding since they are actually simple functions anyway.