Enhance/fix VMS build environment

* config.h-vms.template: make sure the CRTL version is known
* makefile.com: always compile/link the guile module, remove VAXCRTL
parameter, new LIST parameter
* makefile.vms: always compile/link the guile module, use more
complete dependencies
* prepare_vms.com: helper to create a VMS config file when building
from a snapshot of the repository
4 files changed