options: retire 'set backwards' -- it's still recognized but a no-op

doc/nano.texi

@@ -703,7 +703,8 @@ with @code{set backup} or @option{--backup} or @option{-B}.
 The uniquely numbered files are stored in the specified directory.
 
 @item set backwards
-Do backwards searches by default.
+Obsolete option.  Recognized but ignored.  @code{^Q} is available to
+start a backward search.
 
 @item set boldtext
 Use bold instead of reverse video for the title bar, status bar, key combos,

doc/nanorc.5

@@ -74,7 +74,8 @@ with \fBset backup\fR or \fB\-\-backup\fR or \fB\-B\fR.
 The uniquely numbered files are stored in the specified \fIdirectory\fR.
 .TP
 .B set backwards
-Do backwards searches by default.
+Obsolete option.  Recognized but ignored.  \fB^Q\fR is available to
+start a backward search.
 .TP
 .B set boldtext
 Use bold instead of reverse video for the title bar, status bar, key combos,

doc/sample.nanorc.in

@@ -33,9 +33,6 @@
 ## The directory to put unique backup files in.
 # set backupdir ""
 
-## Do backwards searches by default.
-# set backwards
-
 ## Use bold text instead of reverse video text.
 # set boldtext
 

src/nano.c

@@ -2455,6 +2455,7 @@ int main(int argc, char **argv)
 
     /* Initialize the search string. */
     last_search = mallocstrcpy(NULL, "");
+    UNSET(BACKWARDS_SEARCH);
 
     /* If tabsize wasn't specified, set its default value. */
     if (tabsize == -1)