adds org file and gen HTML for HOFs section

	new file:   slides/hofs.html
	new file:   slides/hofs.org
adds slides for HOFs

	modified:   slides/index.html
adds mocha and test for reject

	new file:   exercises/HOFs/hofs.js
	new file:   exercises/HOFs/index.html
	new file:   exercises/HOFs/test.hofs.js
	new file:   exercises/lib/chai.js
new file:   exercises/lib/lodash.js
	new file:   exercises/mocha
adds `every`

	modified:   exercises/HOFs/hofs.js
	modified:   exercises/HOFs/test.hofs.js
adds `mapValues`

	modified:   exercises/HOFs/hofs.js
	modified:   exercises/HOFs/test.hofs.js
adds `findKey`

	modified:   exercises/HOFs/hofs.js
	modified:   exercises/HOFs/test.hofs.js
bit of hierarchy

	modified:   exercises/HOFs/test.hofs.js
full stop!? *twitch*

	modified:   slides/index.html
typo

	modified:   index.html
Merge branch 'master' into hofs

Conflicts:
	slides/index.html

	new file:   assets/promises.ai
	modified:   index.html
	new file:   js/d3.js
	modified:   slides-theme/style.css
	new file:   slides-theme/talk-specific.css
	deleted:    style.css
Merge pull request #1 from funjsldn/hofs

includes HOF section