Updated copyright (to GPL3)

Updated the GNU-LICENSE (to GPL3)

Updated the Makefile.PL with more attributes.

PrintCols.pm:
- added the ability to pass a HASH or HASHREF.
- updated the copyright
- updated some of the documentation

test.pl:
- added -first & -last options to narrow the tests
- rewrote test.pl to have each test with an explicit
  test number.
- Because the tests run are variable and uncertain, had
  to not have a specific plan on "use Test::More", but
  instead use "done_testing(NUM)" at the end.
- added usage() sub to help explain how to run the test program.
- allow test() to be passed HASH, HASHREF, and ARRAYREFs

tests/*.ref:
- updated all the test reference output based on the GNU-LICENSE content.
- added new tests for the ARRAYREF, HASH, and HASHREF test cases.
Created Build.PL script -- the modern way of making Perl modules.

Replaced the Makefile.PL with Build.PL, which creates a Makefile
automatically (if enabled).

Added config to Build.PL to share "tests", so the tests can run.

The html target is now available with Build.PL

Moved PrintCols.pm into lib/Array/PrintCols.pm -- which is where
Build.PL expects it to live.

Regenerated the MANIFEST file, after properly setting certain
non-targets in MANIFEST.SKIP.