Document UseNTorHandshake

doc/tor.1.txt

@@ -1163,6 +1163,16 @@ The following options are useful only for clients (that is, if
     "auto" (recommended) then it is on for all clients that do not set
     FetchUselessDescriptors. (Default: auto)
 
+**UseNTorHandshake** **0**|**1**|**auto**::
+    The "ntor" circuit-creation handshake is faster and (we think) more
+    secure than the original ("TAP") circuit handshake, but starting to use
+    it too early might make your client stand out. If this option is 0, your
+    Tor client won't use the ntor handshake. If it's 1, your Tor client
+    will use the ntor handshake to extend circuits through servers that
+    support it. If this option is "auto" (recommended), then your client
+    will use the ntor handshake once enough directory authorities recommend
+    it. (Default: auto)
+
 **PathBiasCircThreshold** __NUM__ +
 
 **PathBiasNoticeRate** __NUM__ +