Fix building on a brand new system

Require modules rather than use to prevent Build.PL dying before prereq's can be checked
Fix perltidy test

Remove taint mode so $PERL5LIB is used as expected
Exclude Makefile.PL since it doesn't matter if it isn't tidy
Do not use system perl

Use whichever perl is configured first on the users PATH, not the system perl.  This fixes problems when building in a perlbrew environment.