cve-pipeline runs the ceph-dev-pipeline Jenkinsfile, which consults
FORCE to decide whether to rebuild and re-upload when artifacts already
exist in Chacra or Pulp. Without the parameter, env.FORCE is unset and
a CVE rebuild of an already-uploaded sha1 always skips compilation with
no way to override short of THROWAWAY=true.
Also sync the THROWAWAY description with ceph-dev-pipeline's.
Signed-off-by: David Galloway <david.galloway@ibm.com>