Break out validation of arguments for create_entry

[bonehead06]

This change was made to make it easier to understand which argument did not validate. Make the 'create_entry' and 'create_group' methods returned the created object for easier manipulation and re-use of the created object

[bonehead06]

This PR actually has 3 parts.

1. Break out the validation of arguments for create_entry so I could debug what I was doing wrong
2. Return the created group from the create_group method
3. Return the created entry from the create_entry method. Would you like these split into multiple PRs or is it OK to leave all of these as one?

Cheers,

Keith (aka bonehead06)