Remove erroneous File::chdir version dependency

Introduced in commit 9862554f by mistake.
Point to the repository development url
Test passing environment variables with UTF-8 values

Fixes https://rt.cpan.org/Ticket/Display.html?id=81834
Add MANIFEST.SKIP to itself, plus local::lib ./extlib directory
Changes update
Distribution version to 0.80.1_1 for CPANTesters to check
.gitignore update