Support long time intervals in the first block

Support for mInterval('schedule', 'stepsPerInterval', 'c000') > 1. It seems that the initial value of v_state and v_gen especially are not set correctly in this case. A simple fix, when t_jump is not too large, would be to set

tmp_dt = 1 - mInterval('schedule', 'stepsPerInterval', 'c000');
loop(mft_start(mSolve, f, t),
....
    v_state.fx(gn_state(grid, node), f, t + tmp_dt)
        = r_state(grid, node, f, t + tmp_dt);

in 3d_setVariableLimits .