Ideas for elmake:

- add a customize interface
- add elmake-cus-site
- elmake-exportable-site 
  (export all stuff into files than can be transported)
- testcase.elMake (automated testcase)
- backup-variable
- allow converting project.ede to elMakefile
- move packets in/between sites
- allow disabling packets from a site
  (save in customize, per site)
- Targets should be symbols, since that is more lispy.
                 (from Richard M. Stallman)