pyrocufflink: Convert variables file to directory

Converting the *pyrocufflink* group variables definition from a file to
a directory will allow Jenkins jobs to place a Vault-envrypted file
within it that defines the `ansible_become_password` variable. In this
way, a different password can be used for machines that are members of
the *pyrocufflink.blue* domain than for other hosts. The existing
mechanism of specifying the path to the Vault-encrypted file that
defines the variable allows only a single password to be defined, so it
does not work when multiple machines in the same play have different
passwords.

group_vars/pyrocufflink/main.yml

@@ -0,0 +1,5 @@
+krb5_realm: PYROCUFFLINK.BLUE
+samba_use_winbind: true
+pam_winbind: true
+nss_winbind: true
+pam_mkhomedir: true