Update for current version of AKS

[bragma]

Hi, I stringly suggest to inclue this PR since the version of kubernetes specified in the master branch is not available anymore (so it won't work).

Also, notice that in the documentation, this part is incorrect:

password_principal=echo $service_principal|cut -f4 -d ' '

Instead, the password is in column 3 of the table so it should instead be:

password_principal=echo $service_principal|cut -f3 -d ' '