Updating textproc/p5-Text-BibTeX from 0.38 to 0.40

pkgsrc changes:
- Add license definition
- Adjust dependencies
- Add module type

Upstream changes:
Release 0.40 - 7 March, 2010
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* this release is very similar to 0.40_3, but now indexable by cpan.

Release 0.40_3 - 18 February, 2010
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* fixed Build.PL with correct build_requirements;
* fixed test to use still not installed library;

Release 0.40_2 - 15 February, 2010
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* merged btparse library into Text::BibTeX code. I am sorry for all
  other languages that might be using this library. For them my
  suggestion is that they make Text::BibTeX as a dependency.
* ported compilation and configuration tools from ExtUtils::MakeMaker
  to Module::Build.
* back on track, trying to make Text::BibTeX work and compile easily
  on main platforms (sorry, for main platforms I assume Linux, Mac OS
  X and Windows running Strawberry Perl).
* Thanks to Philip Kime for continuous poke so I work on this!!
  Created a THANKS file for this purpose.

(sno)