Add other language nutshells to LEARNING.md
Add other language nutshells to LEARNING.md

exercism/xperl6,mienaikage/xperl6,exercism/xperl6,mienaikage/exercism-perl6,mienaikage/exercism-perl6,mienaikage/exercism-perl6,mienaikage/xperl6,mienaikage/xperl6,exercism/xperl6