Detector coordinates are higher resolution

[habig]

snewpdag/data/detector_location.csv contains detector coordinates.

Noticed while playing with the detector map web page thingy: while the experiments at Kamioka all have the right coordinates to see where the detectors are if you zoom in, at SNOLAB, LNGS, and SURF the detectors all have the same coordinates: the lab buildings, not the underground halls.

A few hundred m isn't going to change the timing fit, but we might as well get it right. The data in the web map is not directly drawn from this file, but will make sure thta gets updated too.

Also, HALO is named HALO-1kt in the file. HALO-1kt doesn't exist yet (ever?) and is at NGS not SNOLAB.