[Japi] More lazy ClassFile parsing checked in

[Jeroen Frijters]

Hi,

I've checked in the first version of lazy class file parsing. This
splits the parsing in two. The first part reads just enough to ascertain
whether a class is public or not, the second part reads the rest. In the
future it may prove worthwhile to split it into more parts, but for the
time being this should at least solve the exceptions that we saw with
IBM's and BEA's libraries.

Regards,
Jeroen