Nix: Make nix repl accept commands ending with semicolon

[srghma]

Actual:

nix-repl> 1 + 2
3

nix-repl> 1 + 2;
error: syntax error, unexpected ';', expecting $end, at (string):1:6

Expected

nix-repl> 1 + 2
3

nix-repl> 1 + 2;
3

Reason:

This will make it easier to paste code chunks from .nix files to nix repl

[edolstra]

I disagree. I think this just leads to confusion about what an expression is. Expressions don't end in semicolons, only attributes do.