docs: document indicator padding option

Add indicator.padding (x, y) to the vimdoc help file and README config
tables.

doc/tags

@@ -19,6 +19,7 @@ watchexec-wxt	watchexec.txt	/*watchexec-wxt*
 watchexec.Config	watchexec.txt	/*watchexec.Config*
 watchexec.Config.auto_scroll	watchexec.txt	/*watchexec.Config.auto_scroll*
 watchexec.Config.indicator	watchexec.txt	/*watchexec.Config.indicator*
+watchexec.Config.indicator.padding	watchexec.txt	/*watchexec.Config.indicator.padding*
 watchexec.Config.indicator.patterns	watchexec.txt	/*watchexec.Config.indicator.patterns*
 watchexec.Config.max_lines	watchexec.txt	/*watchexec.Config.max_lines*
 watchexec.Config.watchexec	watchexec.txt	/*watchexec.Config.watchexec*

doc/watchexec.txt

@@ -177,6 +177,18 @@ indicator (table|nil) ~
     Height of the indicator in screen cells.
     Default: 1
 
+  padding (table|nil) ~
+                                        *watchexec.Config.indicator.padding*
+    Offset from the editor edges. Each value is a number of screen cells.
+
+    x (integer|nil) ~
+      Horizontal offset from the left or right edge.
+      Default: 1
+
+    y (integer|nil) ~
+      Vertical offset from the top or bottom edge.
+      Default: 1
+
   patterns (table|nil) ~
     Lua patterns for detecting command lifecycle in output.
                                    *watchexec.Config.indicator.patterns*