http: avoid empty error messages for some curl errors

diff --git a/RelNotes b/RelNotes
index 00e77229ddadcb8a13b10b693a96bd76a4cb9f33..c301f4c580dbf43de0def9cee43d1eebc1c02c91 120000 (symlink)
--- a/RelNotes
+++ b/RelNotes
@@ -1 +1 @@
-Documentation/RelNotes-1.7.1.txt
\ No newline at end of file
+Documentation/RelNotes/1.7.6.2.txt
\ No newline at end of file