Add support for unknown options in \documentclass in eplbase.cls

[Jimvy]

Context: I was trying to see a document with the draft option (which draws the infamous overfull \hbox explicitly), but it caused an error.
Current problem: in eplbase.cls, all undeclared options are passed through \DeclareOption*, which throws a \ClassError if there is an unknown option.
Proposition: remove this piece of code so that we can pass standard options to the base classes. Maybe we could just keep usereportclass, skiptitle, skiptoc, license instead of intercepting manually the numerous options of LaTeX classes.