move generic template vars to new default layout template #61
refactor engine module to render onebox engine template within default layout template #61
create new layout class to handle template rendering #61
move rendering methods to new layout class, refactor #61
mustache template partials use two curls and gt, not triple curl #61
require layout class in onebox module #61
using mustache instead of handlebars b/c no good support for ruby #61
we want to have a generic name for a class that we will be reusing #61
update templates extension in onebox test to be .mustache #61
use @view as partial in layout template #61
refactor view class to dynamically render as partial template or as layout #61
update #to_html arguments to render layout template #61
escape partial in layout template #61
refactor view class so template isn't created until needed #61
we don't want to create template until it is needed in engine module #61
we want all oneboxes to be created consistently, all with templates #61
we need to override a fake onebox engine's #view method to make tests pass. also delete #template_path test since now in view class #61
attr reader for view needed for fake onebox engines in specs #61
layout template should be only template where triple curl is allowed #61
create spec for view class to test template rendering #61