LossModel.getCombinedG() always adds default value of 1 for total fatalities

[mhearne-usgs]

Our combined G value is going to be off by a little bit because we're passing in a loss dictionary which contains total losses. the getModel() method treats "TotalDollars" as a country code it doesn't know about and assigns it an L2G value of 1.0.

This means for a lossdict that looks like: {'EU': 0, 'WU': 68376, 'TotalDollars': 68376}

you get a combined G of 2.69 where it should be 2.5 (the L2G value for WU).