[svn r330] Implemented synchronized statements. Changed the tryfinally handlers to a more generalized EnclosingHandler. Changed ClassInfoS to be mutable so they can be used as locks. Added new BB after throw ala return/break etc.

module tangotests.nested1;

void main()
{
    int i = 42;
    assert(i == 42);
    void func()
    {
        assert(i == 42);
    }
    func();
}