Add JavaScript::SpiderMonkey to ecosystem

See https://github.com/hartenfels/Javascript-SpiderMonkey

Author: Carsten Hartenfels

META.list

@@ -461,3 +461,4 @@ https://raw.githubusercontent.com/p6-pdf/perl6-PDF-Tools/master/META.info
 https://raw.githubusercontent.com/pierre-vigier/Perl6-HTTP-Signature/master/META.info
 https://raw.githubusercontent.com/jonathanstowe/WebService-Soundcloud/master/META.info
 https://raw.githubusercontent.com/Demayl/perl6-Email-Valid/master/META.info
+https://raw.githubusercontent.com/hartenfels/JavaScript-SpiderMonkey/master/META.info