[m-rev.] diff: make --warn-inconsistent-pred-order-clauses the default

[Julien Fischer]

On Tue, 27 Aug 2019, Zoltan Somogyi wrote:

> The one question I have about this is for Julien, since he did the original work
> on underscores in numbers: is base_string_to_int_underscore worth keeping
> around, even though it is unused?

No, it was only ever intended for use by the lexer and that stopped using it
in commit a56c4f5.  It can be removed.

Julien.