Add a pprint long name for pp command, useful when masked by any pp variable in scope

[goodboy]

The pretty print command pp in the repl doesn't seem have an equivalent long name (like pprint) and is covered by the so called smart command parsing.

!!pp obviously works but i think a long name might be handy?

[oxtna]

Isn't this basically the same as making an alias in the configuration file, i. e.

class Config(pdb.DefaultConfig):
    [...]
    def setup(self, pdb):
        Pdb = pdb.__class__
        Pdb.do_pprint = Pdb.do_pp

?