Feature: Add options for enforcing asset name validation (Touches #11473)

[cram42]

Touches issue #11473
We (and several others apparently) use the Asset Name as the primary identifier for assets.
Therefore it's required to be mandatory, in a specific format, and unique forever.
We also do have some assets without a name, so null values are allowed.

I've put together this quick little commit to add those options into General Settings.

Validation Checkbox - Enables the regex validation rule on asset names.
Regex Input - The regex rule itself.
Unique Checkbox - Enables the unique_undeleted rule on asset names.
Ignore Blank Checkbox - Enables the nullable rule on asset names.

For those in #11473 who are happy to just have it mandatory, enable Validation, set Regex to regex:/^.+$/, and disable Ignore Blank.

[cram42]

Extremely confused about the failed checks. Is develop branch broken for anyone else at the moment?