added a description of former and current repos

REPOSITORIES

+Overview of former and current tlibs repositories
+-------------------------------------------------
+
+- From 2019 till now:
+	https://code.ill.fr/scientific-software/takin/tlibs
+	https://code.ill.fr/scientific-software/takin/tlibs2
+	Main development repositories for tlibs 1/2.
+
+- From 2016 till 2019:
+	https://github.com/t-weber/tlibs
+	Private repositoriy for tlibs 1.
+
+- From 2015 till 2017:
+	https://forge.frm2.tum.de/cgit/cgit.cgi/frm2/mira/tlibs.git/
+	Former main development repository for tlibs 1.