Fix criteria for valid user data

[ahaurat]

Fixes #1107 to allow username or email to identify a user in addition to id or ip_address.

[Jean85]

Thank you for your PR; please add at least a test and a changelog entry.

[ste93cry]

@ahaurat after the answer of @kamilogorek in the referenced issue, there is some more work to do, if you are willing to contribute it. We should:

• deprecate the static named constructors which only purpose was to ensure that the object was created in a consistent state with the minimum amount of required information
• remove all validation logic that assumes that either the ID or the IP address fields must be set
• make the constructor public and add all the arguments to it

In the next major version considering that none of the attributes of the UserDataBag class is required we can probably replace its usages with a simple plain array

[stayallive]

@ahaurat I hope you don't mind me jumping in making changes so we can push this over the finish line 👍

After a discussion with @ste93cry we've decided to not deprecate the static named constructors yet, we might do that later and just keep them as nice ways to quickly construct a user data bag.

[ahaurat]

@stayallive no problem at all; thanks for tackling it. Apologies I didn't have time to get to it this week.