Faulty header line not conform perl specs

[hoelzro]

https://github.com/petdance/ack/issues/195

[petdance]

• If you're installing with the CPAN toolchain, then the CPAN toolchain modifes the shebang line.

~/ack2 $ head -1 blib/script/ack
#!/var/perl588/bin/perl

• If you're building the ack-standalone, that's built with /usr/bin/env

$ head -1 ack-standalone
#!/usr/bin/env perl

• If you're building from a package, that's up to the packagers what goes in the shebang, and that's outside of my control.