Generalize `elif-else` to all compound statements

Even if it will, it is not of significance. Best to leave this as part of “small benefits that might happen during implementation” and not part of the decision regarding this.

This seems to be the consensus so far and I agree. Thus, I have reduced this proposal to: `while-elif-else`, `for-elif-else`, `try-except-elif-else` - #8 by elis.byberi