Specify JSON::PP explicitly when fatpacking

Otherwise it won't be fatpacked when building on Perl 5.14 or higher,
which includes JSON::PP in core.  To support older Perl's, we explicitly
specify it.
Move ExtUtils::MakeMaker into a configure-only requirement
We don't care about configure, build, or test phase deps during fatpack
Don't bother showing the pod files we remove from fatlib/
Report un-copied but traced modules

These are mostly OK to ignore, but may also raise an eyebrow if
something unexpected pops up.

(For example, it revealed that Date::Manip uses %+ which is a Perl 5.10
feature (via Tie::Hash::NamedCaptures).  Luckily for us, the DM5 backend
doesn't require 5.10.)