Annotations for 13C are not wide enough

[lpatiny]

Would be nice if the annotations where maybe 1 ppm in the case of 13C prediciton.

Currently they are too narrow.

http://www.cheminfo.org/Spectra/NMR/Predictions/13C_Prediction/index.html?viewURL=https%3A%2F%2Fcouch.cheminfo.org%2Fcheminfo-public%2Fb50564ac9d207212f8e5ae8167a45f3c%2Fview.json%3Frev%3D18-61ab71a34ec02918f53a7b6aa60dec42

But maybe this should be migrate and add the methods in the "Sample" visualizer helper project. There could be 1H NMR spectra prediction (with direct access to spinus), 13C, ....