Add contact/lead deletion by ID and User ID

[thewheat]

• Allow direct contact/lead deletion by ID / user_id value
• Make existing .delete(contact) smarter
  • if no id but has user_id do deletion by user_id
  • throw an exception if no identifiers
• Adding the new setID and setUserID functions coincidentally allows better updating of contacts as well
  • previously you had to find a contact, make changes to that object and update that contact
  • now you can create a contact object and update directly simplifying and reducing API calls

[choran]

LGTM 👍

[choran]

@thewheat I think this looks great. I guess it is an unrelated question but I was checking for hard delete. I know that is not available via the leads endpoint but was just looking in the Java SDK and noticed that it is here but not shown in the readme. I need to add some info on that so people are aware of it. I just wanted to check if you were aware of any reason we did not add the info in the readme?
I will merge this. I will likely do a release next week

[thewheat]

@choran back for holidays here. Not sure I get what you mean there about not adding the info in the readme. Are you referring to user hard deletes? I think that was just missed out on so definitely worth adding 👍

Added to this issue #227 so we wont' forget