Replace all uses of assert with Exceptions

[Nava2]

assert is widely considered bad. It corrupts the stack and does not behave "appropriately."

All assert messages should be replaced with this or equivalent:

From:

assert module instanceof RegisterArray :
               "Passed non-RegisterArray to RegisterArray.copyDataTo()" ;

To:

checkArgument(module instanceof RegisterArray, "Passed non-RegisterArray to RegisterArray.copyDataTo()");