Function bd_wgs2mkt 

pub fn bd_wgs2mkt(bdwgs: (f64, f64)) -> (f64, f64)

bd_wgs2mkt 将百度经纬度坐标(BD-09) 转换至 百度墨卡托坐标

    let (x, y) = coord_transform::bd_wgs2mkt((118.0, 32.0));
    assert_eq!(x, 13135842.840674074);
    assert_eq!(y, 3740459.445338771);