Module-wide description field validation

[ba1ciu]

We allow any utf-8 string of length up to 256 characters in description fields.

Implement the check in new utils/validation.go file in a similar manner to how it was done for name validation. For reference, see the name implementation here: #454

[aljo242]

@gjermundgaraba @ba1ciu starting this

[aljo242]

@ba1ciu @gjermundgaraba by "alpha numeric" do you mean literally only the characters:

abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789

I think it might be useful to allow for more characters than this such as punctuation, brackets, etc..

[gjermundgaraba]

@aljo242, yeah you are right, it should be utf-8 string.