Robinson projection (ESRI:54030) test failed

[Yaqiang]

Following test for Robinson projection failed.

    @Test
    public void testRobinson() {
        checkTransform("+proj=latlong +datum=WGS84", -30, 40, "+proj=robin +datum=WGS84", -2612095.95, 4276351.58, 2e-1);
        checkTransformFromWGS84("ESRI:54030", -30., 40., -2612095.954698802, 4276351.583838239);
        checkTransformToWGS84("ESRI:54030", -2612095.954698802, 4276351.583838239, -30., 40., 1E-4);
    }

[Yaqiang]

I have solved the above bug and commit it to my proj4j forking repository (Yaqiang@42fa692) refering to the code of PROJ (https://github.com/OSGeo/PROJ/blob/master/src/projections/robin.cpp). But my last PR #86 was not reviewed and accepted, so I don't know to to commit a new PR now.

[Yaqiang]

Solved by PR #86