Switch template encoding to utf-8

The default template encoding is now utf-8.  Previously, the encoding was
"ascii", which was standard throughout Python 2.   This allows that
"magic encoding comment" for utf-8 templates is no longer required.

Fixes: #267
Change-Id: I411a75ebd6161e2517e06b5180a3571e5f5d923e
8 files changed