patch 8.1.0717: there is no function for the ":sign jump" command
Problem: There is no function for the ":sign jump" command.
Solution: Add the sign_jump() function. (Yegappan Lakshmanan, closes #3780)
diff --git a/runtime/doc/usr_41.txt b/runtime/doc/usr_41.txt
index 343d476..c7bfffd 100644
--- a/runtime/doc/usr_41.txt
+++ b/runtime/doc/usr_41.txt
@@ -987,6 +987,7 @@
sign_define() define or update a sign
sign_getdefined() get a list of defined signs
sign_getplaced() get a list of placed signs
+ sign_jump() jump to a sign
sign_place() place a sign
sign_undefine() undefine a sign
sign_unplace() unplace a sign