Adding an automated test for POD correctness.

Adding an automated test for POD correctness.

This test script checks all perl files in the C4 directory for POD correctness. It is
completely optional, and as of yet, is not actually run when you run the test suite.
It's just a handy way to check our POD documentation, which should be correct before
we release code.

This script can be invoked with 'prove -v xt/author/podcorrectness.t'

Additionally, this is the first test in the 'xt' directory. Current perl testing practices
have reserved the 'xt' directory for tests that should be run by the code authors before
release. See:
http://perl-qa.hexten.net/wiki/index.php/Oslo_QA_Hackathon_2008_:Achievements#Testing_Best_Practices
for more information.

Signed-off-by: Joshua Ferraro <jmf@liblime.com>