* module/language/c99/compiler.mes (int->bv): New function.
(init->data): Use it. Add parameter. Update callers.
(array-init->data): Add type parmeter.
(array-init-element->data): Likewise.
* module/mes/bytevectors.mes (bytevector-u8-set!): New function.
* module/mes/bytevectors.scm (mes): Export it.
* module/mes/as.mes (int->bv8): New function.
