Enhances most of the messages for the end users.
Two major changes can be noticed:
1. In most cases no class name will be written in the message; it
prevents users that potentially have no access to the codebase to
get a useless/unclear information.
2. The input values are now properly formatted; for instance a string
value will now be written directly instead of the type `string`;
arrays are also handled with the array shape format, for instance:
`array{foo: 'some string'}`.
