Added function for defining ensure-generic-function in run-time environment R2.
Added function for defining ensure-generic-function in run-time environment R2.

clasp-developers/SICL,vtomole/SICL,vtomole/SICL,vtomole/SICL,vtomole/SICL,clasp-developers/SICL,clasp-developers/SICL,clasp-developers/SICL