fix Vagrant 1.1 double quotes from ssh-config
fix Vagrant 1.1 double quotes from ssh-config

Vagrant 1.1 introduces leading and trailing whitespaces for IdentityFile when queried with ```vagrant ssh-config```
this leads to

```
IOError: [Errno 2] No such file or directory: '"/Users/xyz/.vagrant.d/insecure_private_key"'
```

this patch removes the double quotes and keeps backward compatibility
ahnjungho/fabtools,pombredanne/fabtools,fabtools/fabtools,sociateru/fabtools,ronnix/fabtools,badele/fabtools,n0n0x/fabtools-python,hagai26/fabtools,AMOSoft/fabtools,bitmonk/fabtools,wagigi/fabtools-python,davidcaste/fabtools,prologic/fabtools