Perl5-Alien/Alien-Base — pull request #61 by plicease (2014-09-05 00:07:56+00:00)
Title: use pure perl PkgConfig.pm if pkg-config is not available

This does two things:

1. makes the pure perl `pkg-config` implementation `PkgConfig.pm` a prereq if `pkg-config` cannot be found in the PATH.
2. use `PkgConfig.pm` if `pkg-config` is not available at runtime, preferring a real system `pkg-config`

PkgConfig.pm is being actively developed by myself (patches welcome) and is included with Strawberry Perl as of 5.20. It is also useful on systems where pkg-config is not installed by default (which is actually almost everywhere).

It does NOT replace `Alien::Base::PkgConfig`, although we should maybe consider this down the road if there are sufficient advantages.