This eliminates one temporary directory in the process.

Signed-off-by: Michael Hanselmann <hansmi@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>

docbook-wrapper had the names for the docbook2* programs hardcoded. This
patch changes Makefile.am and the wrapper script to pass them via
another argument.

Another issue where rapi.in was built before rapi-resources.sgml is
also fixed.

Reviewed-by: iustinp

At least docbook2man inserts a date formatted using the current
locale into its output.

Reviewed-by: iustinp

This change allows us to use cleaner dependencies between
directories. The build system is basically rewritten in large parts
and may contain bugs.

Reviewed-by: iustinp