Example error in createdb doc

Hello,

I believe I've found an incorrect example in the createdb documentation:
https://www.postgresql.org/docs/current/static/app-createdb.html

The example given for createdb fails because template0 is not provided:

[~] createdb -p 5000 -h eden -E LATIN1 -e demo
CREATE DATABASE demo ENCODING 'LATIN1';
createdb: database creation failed: ERROR: new encoding (LATIN1) is
incompatible with the encoding of the template database (SQL_ASCII)
HINT: Use the same encoding as in the template database, or use template0
as template.

I've attached a patch that addresses the issue.

Thanks!

--
Jason O'Donnell
Crunchy Data Solutions