Add support for passing configuration profile

Add support for passing configuration profile

The new option --config-profile accepts a INI style file, so that
installation options are passed in via a file. this is useful for
testing and automated installs.

This file can have 2 sections: globals, arguments.

The globals section can change global variable in the install script
like: TEMPLATES, CONFDIR, DATADIR, HTTPDCONFD and so on, so that an
installation can use non-standad directories.

The argumets section accepts any argument option.
The config profile file is parsed after all arguments have parsed and
can override any plugin argument.

Signed-off-by: Simo Sorce <simo@redhat.com>