Pros:
* <obinit> no longer emitted: one less function per class
* Parameters to the primary constructor, if any, are no longer referred to out of scope
* Simple primary constructor `val` and `var` declarations work as expected
Cons:
* If there are multiple secondary constructors, no primary constructor and long init blocks, there could be considerable duplicate extraction of those init blocks. Hopefully this case is very rare.
* Extract varargs as if they are ordinary positional arguments
* Adapt the QL that distinguishes varargs from ordinary arguments to account for Kotlin's varargs which can occur in the middle of the arg list
* Add a test checking dataflow through varargs which doesn't work yet due to array-get and array-set not being extracted as IndexExprs
* Extract the special case arrayOf(*x) as a clone call, which is (equivalent to) the Java lowering of that operation
