Remove ssh_wait_timeout from doc basic examples for virtualbox/vmware builders. Fixes GH-2382.

website/source/docs/builders/virtualbox-iso.html.markdown

@@ -33,7 +33,6 @@ Ubuntu to self-install. Still, the example serves to show the basic configuratio
   "iso_checksum_type": "md5",
   "ssh_username": "packer",
   "ssh_password": "packer",
-  "ssh_wait_timeout": "30s",
   "shutdown_command": "echo 'packer' | sudo -S shutdown -P now"
 }
 ```

website/source/docs/builders/virtualbox-ovf.html.markdown

@@ -39,7 +39,6 @@ the settings here.
   "source_path": "source.ovf",
   "ssh_username": "packer",
   "ssh_password": "packer",
-  "ssh_wait_timeout": "30s",
   "shutdown_command": "echo 'packer' | sudo -S shutdown -P now"
 }
 ```

website/source/docs/builders/vmware-iso.html.markdown

@@ -38,7 +38,6 @@ Ubuntu to self-install. Still, the example serves to show the basic configuratio
   "iso_checksum": "af5f788aee1b32c4b2634734309cc9e9",
   "iso_checksum_type": "md5",
   "ssh_username": "packer",
-  "ssh_wait_timeout": "30s",
   "shutdown_command": "shutdown -P now"
 }
 ```