Correct the dependancy information

Test::Compile actually requires:
* File::Spec (core since 5.4.5)
* Test::Builder (core since 5.6.2)
* UIVERSAL::require (not core)
* version (core since 5.6.9)

It is now documented as requiring:
* Perl 5.6.2 (includes File::Spec & Test::Builder)
* UIVERSAL::require (not core)
* version (core since 5.6.9)