Add add_template, add_template_var, add_arch_template, and
add_arch_template_var to the call for lorax.get_lorax_cmd for the Atomic
ISO composes.
Remove duplicate if statement for add_template_var in lorax wrapper
CHANGE: Rename product_* config options to release_* for consistency with productmd.
ACTION: Rename product_name, product_short, product_version, product_is_layered to release_* in config files.
Rename //variant/product to //variant/release in variants XML.