This PR moves the "iso_checksum_type" field that is explicitly defined as "sha1" in all the builders into the user-variable section for all of the templates. We already allow the user to specify the "iso_checksum" as a user-variable which allows its customization. So by exposing the checksum type as well, this allows the user to choose whatever checksum they see fit. This allows the user complete control over the iso, its checksum, and its checksum type when building the template.
Each of the builders in all of the templates use a default value of "sha1" for the "iso_checksum_type", so this was used for the default value of the "iso_checksum_type" user variable in order to retain backwards compatibility.
This PR moves the "iso_checksum_type" field that is explicitly defined as "sha1" in all the builders into the user-variable section for all of the templates. We already allow the user to specify the "iso_checksum" as a user-variable which allows its customization. So by exposing the checksum type as well, this allows the user to choose whatever checksum they see fit. This allows the user complete control over the iso, its checksum, and its checksum type when building the template.
Each of the builders in all of the templates use a default value of "sha1" for the "iso_checksum_type", so this was used for the default value of the "iso_checksum_type" user variable in order to retain backwards compatibility.