refspec: factor out parsing a single refspec

diff --git a/RelNotes b/RelNotes
index 6205f6cd4f83a45883ddc46824aeb050e5a59237..f6c58b347fd8338482625ea11ec1802baa6ea068 120000 (symlink)
--- a/RelNotes
+++ b/RelNotes
@@ -1 +1 @@
-Documentation/RelNotes/1.7.11.7.txt
\ No newline at end of file
+Documentation/RelNotes/2.18.0.txt
\ No newline at end of file