current with latest freerouter's clearance support

        int     curTrackWidth = aBoard->m_BoardSettings->m_CurrentTrackWidth;

        int     curTrackWidth = aBoard->m_BoardSettings->m_CurrentTrackWidth;

        int     curTrackClear = aBoard->m_BoardSettings->m_TrackClearence;

        int     curTrackClear = aBoard->m_BoardSettings->m_TrackClearence;

        // The 0.5 is to give freerouter a little extra room, this is 0.5 mils.

        // Add .1 mil to the requested clearances as a safety margin.

        // If we export without this, then on import freerouter violates our

        // There has been disagreement about interpretation of clearance in the past

        // DRC checks with track to via spacing, although this could be a

        // between Kicad and Freerouter, so keep this safetyMargin until the

        // result of > testing vs. >= testing in PCBNEW's DRC.

        // disagreement is resolved and stable.  Recently Kicad started adding

//       double  safetyMargin = 0.5;

        // 0.1 mils to what it is given, so we can use zero for now.

        const double  safetyMargin = 0.0;

        // recent freerouter code adds .1 to the requested clearances, and I want .5

        // so subtract .1 so we actually get 0.5.

        double  safetyMargin = 0.4;

        double  clearance = scale(curTrackClear);

        double  clearance = scale(curTrackClear);

        rules.push_back( rule );

        rules.push_back( rule );

        // On a high density board, a typical solder mask clearance will be 2-3 mils.

        // On a high density board, a typical solder mask clearance will be 2-3 mils.

        // This exposes 2 to 3 mils of bare board around each pad.  So we need at least

        // This exposes 2 to 3 mils of bare board around each pad, and would

        // 2 mils *extra* clearance for tracks which would come near a pad on

        // leave only 1 to 2 mils of solder mask between the solder mask's boundary

        // to the edge of any trace within "clearance" of the pad.  So we need at least

        // 2 mils *extra* clearance for traces which would come near a pad on

        // a different net.  So if the baseline trace to trace clearance was say 4 mils, then

        // a different net.  So if the baseline trace to trace clearance was say 4 mils, then

        // the SMD to track clearance should be at least 6 mils.  Then, because

        // the SMD to trace clearance should be at least 6 mils.  Also add our safetyMargin.

        // freerouter seems to be off about a 1/2 mil on clearance tests, add

        sprintf( rule, "(clearance %.6g (type default_smd))", clearance + 2.0 + safetyMargin );

        // another .5 mil for this test discrepancy as a safety margin.

        sprintf( rule, "(clearance %.6g (type default_smd))", clearance + safetyMargin + 2.0 );

        rules.push_back( rule );

        rules.push_back( rule );

        /* see: http://www.freerouting.net/usren/viewtopic.php?f=5&t=339#p474

        /* see: http://www.freerouting.net/usren/viewtopic.php?f=5&t=339#p474