completion: make compatible with zsh

diff --git a/RelNotes b/RelNotes
index da6e81321a332fc7c7229c04e438f4161f27755d..0e11dea6d0d1b888ddfc2825bb197aae8027d459 120000 (symlink)
--- a/RelNotes
+++ b/RelNotes
@@ -1 +1 @@
-Documentation/RelNotes-1.6.1.2.txt
\ No newline at end of file
+Documentation/RelNotes-1.7.3.txt
\ No newline at end of file