Add data for Chapter 27.
Get clickable axis labels working with latest NVD3.
Move utility functions into an Angular service.
Move utility functions into an Angular service.

Convert chartFactionsStream into an Angular directive.
Edit comment.
Semicolons.
Convert chartCombatants and chartDeaths into Angular directives.
Spacing.
Convert chartCoappear into an Angular directive.
Remove commented lines.
Load only source files under test.