Added xml file validation to the aci_rest module

[sajagana]

Note:

Removed unwanted code from the aci_rest module and add xml file validation tasks.

[sajagana]

what would happen in scenario rest_type json, output_format xml?

If rest_type is JSON, It will ignore the output_format check.

And the output_format supports only XML file/string. It won’t support rest_type JSON.