Overloaded several atoms that error on string input

[dylannrees]

A Upper case.
C Swap case .
N Lower case.
İ chr(ord(z) + 1).
Ị chr(ord(z) - 1).
Ẓ Index of z in Jelly's code page (unaliased ÆP). Still is a prime test for numerical argument.
‘ Next character in Jelly's code page.
’ Previous character in Jelly's code page.
Ä Map list to result when z is a string. Before this change, “ab”Ä would result in ['a', 'ab'] but now results in [['a'], ['a', 'b']].

A, C and N vectorize at depth 0 unlike Œu, etc. The rest of the atoms above were overloaded with commands of atoms of the same depth.