fixes for specific cases (pole, ellipsoid, sphere) : aea, aeqd : ellipsoid...

fixes for specific cases (pole, ellipsoid, sphere) : aea, aeqd : ellipsoid case added cea : ellipsoid and sphere cases rewriting omerc : use of no_rot, no_off, lon_1 and lon_2 parameters stere : pole case added, use of lat_ts cass : pole case added. See ticket #80