gddo-server: consolidate template initialization

This is in preparation for passing around the template map explicitly
instead of using it as a global.  It also moves the manifest of template
sets into templates.go and out of main.go.

Change-Id: Ic7db8d5ab0186c1f4eb2446871e2c18ae1554d82
Reviewed-on: https://go-review.googlesource.com/67051
Reviewed-by: Tuo Shan <shantuo@google.com>
2 files changed