Adds definition for Repository

Author: JJ

doc/Language/glossary.pod6

@@ -709,6 +709,12 @@ means "Paradise."
 =head1 Repository
 X<|Repository>
 
+A filesystem under control of a source control management application, usually git,
+that holds the sources for a project, library or application. This file, for
+instance, is in L<a GitHub repository|https://github.com/perl6/doc>. Repositories store not only
+files, but also history of changes and can be used by the developing
+or writing team for interaction through issues or comments to code. 
+
 =head1 roast
 X<|roast>