Remove incorrect amend-entire example

[rianoc]

The example is incorrect:

q)@[1 2; ::; ,; 3 4 5]
1 2 3 4 5

It produces a length error:

q)@[1 2; ::; ,; 3 4 5]
'length
  [0]  q)@[1 2; ::; ,; 3 4 5]

As:

q),'[1 2;3 4 5]
'length
  [0]  ,'[1 2;3 4 5]
        ^

The bad example has been removed.

A new example better showing :: devolving to ' has been added:

@[(1 2;4 5); ::; ,; 3 6]
1 2 3
4 5 6