Add '-T' switch to the SSH connectivity check examples

Since the upgrade of apache mina in If047c3a279fc9c98a59ac3102b0db3f5f2fdae48
the SSH connectivity check which we recommend in our documentation
didn't work:

$ ssh admin@localhost -p29418
Bad packet length 1184572426.
ssh_dispatch_run_fatal: Connection to ::1: message authentication code incorrect

I could reproduce this error from both OSX and Linux. Using the -T option
fixes the issue.

This issue only affected the SSH connectivity check. All SSH commands
work without the -T swith and git-over-http also works.

Change-Id: I97148b2700ad9927b4e96a38dcbf7243f7f53ead

Documentation/config-login-register.txt

@@ -116,7 +116,7 @@ are entered in the middle of the RSA string.
 Verify that the ssh connection works for you.
 
 ----
-  user@host:~$ ssh user@localhost -p 29418
+  user@host:~$ ssh user@localhost -p 29418 -T
   The authenticity of host '[localhost]:29418 ([127.0.0.1]:29418)' can't be established.
   RSA key fingerprint is db:07:3d:c2:94:25:b5:8d:ac:bc:b5:9e:2f:95:5f:4a.
   Are you sure you want to continue connecting (yes/no)? yes

Documentation/error-permission-denied.txt

@@ -29,7 +29,7 @@ This command will print out a detailed trace which is helpful to
 analyze problems with the SSH authentication:
 
 ----
-  $ ssh -vv -p 29418 john.doe@git.example.com
+  $ ssh -vv -T -p 29418 john.doe@git.example.com
 ----
 
 If the SSH authentication is successful you should find the following

Documentation/user-upload.txt

@@ -82,7 +82,7 @@ port 29418, using the same hostname as the web server:
 
 ====
 ..................................................................
-  $ ssh -p 29418 sshusername@hostname
+  $ ssh -T -p 29418 sshusername@hostname
 
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