Use Gobo FreeELKS version when GOBO_EIFFEL is ge

This is therefore closer to the original xace files.
 
This uses 2 ecf files that Eric introduced in commit 26cf09b71b41c1a856dc451634eb4b332cc9cd89
* $GOBO/library/free_elks/library.ecf
* $GOBO/library/kernel/library.ecf

The other commits are just the result of a merge with the latest version of Gobo