setup_pager: set GIT_PAGER_IN_USE

diff --git a/RelNotes b/RelNotes
index e13dbd4f9fa071eb6b6dfba591d4e4f4fb6fef95..5a33236ce993853babae09bf228c9cd33b0ac808 120000 (symlink)
--- a/RelNotes
+++ b/RelNotes
@@ -1 +1 @@
-Documentation/RelNotes-1.5.4.5.txt
\ No newline at end of file
+Documentation/RelNotes/1.7.6.1.txt
\ No newline at end of file