Update p5-PPI from version 1.212 to version 1.213.

Upstream changes:
1.213 Tue  6 Jul 2010
Summary:
- Targetted bug fix, no changes to parsing or normal usage

Details:
- Updated to Module::Install 1.00
- Updated module depednencies in xt author tests
- Fixed extremely broken PPI::Token::Pod::merge and added test case

(seb)