Moo::_Utils: import Exporter's import instead of inheriting

This requires Exporter 5.57 (from perl 5.8.3+ or CPAN).
Sub::{Defer,Quote}: import Exporter's 'import' instead of inheriting

And by the way, remove one usage of base.pm.
'use base ...' replaced with 'our @ISA = ...'

Rationale:
- if the whole application uses only Moo(se), 'extends' will (or should) be used
  elsewhere, not 'use base'. So let's remove our usage of base.pm to
  avoid any loading of it in the whole app.
- base.pm is crufty (See HISTORY in parent.pm). parent.pm should be used
  nowadays (because in core since 5.10.1, and available on CPAN).
Merge branch 'no-base-pm'