patch 8.2.4825: can only get a list of mappings

Problem:    Can only get a list of mappings.
Solution:   Add the optional {abbr} argument. (Ernie Rael, closes #10277)
            Rename to maplist().  Rename test file.
diff --git a/runtime/doc/usr_41.txt b/runtime/doc/usr_41.txt
index 12d3adc..89fca8d 100644
--- a/runtime/doc/usr_41.txt
+++ b/runtime/doc/usr_41.txt
@@ -1089,10 +1089,10 @@
 	digraph_getlist()	get all |digraph|s
 	digraph_set()		register |digraph|
 	digraph_setlist()	register multiple |digraph|s
-	getmappings()		get list of all mappings
 	hasmapto()		check if a mapping exists
 	mapcheck()		check if a matching mapping exists
 	maparg()		get rhs of a mapping
+	maplist()		get list of all mappings
 	mapset()		restore a mapping
 	menu_info()		get information about a menu item
 	wildmenumode()		check if the wildmode is active