Refactor template rendering code
Refactor template rendering code

- Create classes for each type of code example
- Use ERB for template rendering

Signed-off-by: Bebe Peng <cc70e5ee229c0d4b3ccc63a88c70622c84c389ff@pivotal.io>

sbrady/hologram,trulia/hologram,hideki-a/hologram,askl56/hologram,electronspin/hologram,donnoman/hologram,hunj/hologram,hunj/hologram,hideki-a/hologram,mike6398/hologram,landsurveyorsunited/hologram,askl56/hologram,angelabier1/hologram,angelabier1/hologram,trulia/hologram,donnoman/hologram,electronspin/hologram,mike6398/hologram,sbrady/hologram,landsurveyorsunited/hologram