options: rename long version of -K from --rebindkeypad to --rawsequences

To better describe what it does, and to have full contrast with the
--rebinddelete option: the latter can now be shortened to --rebind
without getting a conflict, and --rawsequences can be abbreviated
to simply --raw and still make sense.

doc/nano.1

@@ -101,7 +101,7 @@ executed commands, so they can be easily reused in later sessions.
 .BR \-I ", " \-\-ignorercfiles
 Don't look at the system's \fInanorc\fR nor at the user's \fInanorc\fR.
 .TP
-.BR \-K ", " \-\-rebindkeypad
+.BR \-K ", " \-\-rawsequences
 Interpret the numeric keypad keys so that they all work properly.  You
 should only need to use this option if they don't, as mouse support
 won't work properly with this option enabled.

doc/nano.texi

@@ -191,7 +191,7 @@ executed commands, so they can be easily reused in later sessions.
 Don't look at the system's nanorc file nor at the user's nanorc.
 
 @item -K
-@itemx --rebindkeypad
+@itemx --rawsequences
 Interpret the numeric keypad keys so that they all work properly.  You
 should only need to use this option if they don't, as mouse support
 won't work properly with this option enabled.
@@ -839,7 +839,7 @@ Interpret the Delete key differently so that both Backspace and Delete
 work properly.  You should only need to use this option if Backspace
 acts like Delete on your system.
 
-@item set rebindkeypad
+@item set rawsequences
 Interpret the numeric keypad keys so that they all work properly.  You
 should only need to use this option if they don't, as mouse support
 won't work properly with this option enabled.

doc/nanorc.5

@@ -206,7 +206,7 @@ Interpret the Delete key differently so that both Backspace and Delete
 work properly.  You should only need to use this option if Backspace
 acts like Delete on your system.
 .TP
-.B set rebindkeypad
+.B set rawsequences
 Interpret the numeric keypad keys so that they all work properly.  You
 should only need to use this option if they don't, as mouse support
 won't work properly with this option enabled.

doc/sample.nanorc.in

@@ -130,7 +130,7 @@
 # set rebinddelete
 
 ## Fix numeric keypad key confusion problem.
-# set rebindkeypad
+# set rawsequences
 
 ## Do extended regular expression searches by default.
 # set regexp