Class reference searching

[shellderp]

need a way to find references to a given class. one way would be to search for ConstantClass entries that have the classes name. could implement constant reference search, and use it for this

add to class context menu

[shellderp]

more specifically, a good way would be to have a findConstantReferences function that searches for all references to a constant in a given class, but checks if the classes constantpool contains it before finding references

then this function can be called on all loaded classes, and will still be efficient (won't search methods if the constant isn't even used in the class)