* New language feature: with expressions.

The expression `with E1; E2' evaluates to E2 with all bindings in
  the attribute set E1 substituted.  E.g.,

    with {x = 123;}; x

  evaluates to 123.  That is, the attribute set E1 is in scope in E2.

  This is particularly useful when importing files containing lots
  definitions.  E.g., instead of

    let {
      inherit (import ./foo.nix) a b c d e f;

      body = ... a ... f ...;
    }

  we can now say

    with import ./foo.nix;

    ... a ... f ...

  I.e., we don't have to say what variables should be brought into scope.

corepkgs/buildenv/builder.pl.in

@@ -27,7 +27,7 @@ sub createLinks {
             $srcFile =~ /\/nix-support$/ ||
             $srcFile =~ /\/log$/)
         {
-            # Do noting.
+            # Do nothing.
 	}
 
         elsif (-d $srcFile) {