[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 classinfo2;

class C
{
}

class D : C
{
}

void main()
{
    D d;
    d = new D;
    ClassInfo ci = d.classinfo;
    assert(ci is D.classinfo);
}