[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 neg;

void main()
{
    int i = 32;
    long l = 55;
    float f = 23;
    double d = 4;
    assert(-i == -32);
    assert(-l == -55);
    assert(-f == -23);
    assert(-d == -4);
}