Remove proposed (but unimplemented) $foo ~~ Range smart matching.

Remove proposed (but unimplemented) $foo ~~ Range smart matching.

The reasons for that are :

- $_ ~~ 1..42 actually parses as ($_ ~~ 1) .. 42
- in when(), a range 1..42 will be expanded, and not treated as a
  boolean flip-flop operator
- It will not distribute properly with array smart-matching, as
  in $foo ~~ [1, 2, [4..5]] (that won't match for $foo = 4.2 for
  example.)