[patch] pg_ctl init extension

Attached patch extends pg_ctl command with init option. 

pg_ctl -D /var/lib/postgres [-s] init

This should replace usage of initdb command which has problematic name
as we already discussed several times. Initdb binary will be still
there, but it can be renamed and move into execlib dir in the future.

Patch does not contains documentation changes. They will depends on
decision which database initialization method will be preferred.



	Zdenek