NYX - fix sample axes in epx.db to match xyz directions on AMX/FMX

use the x, y, z axis directions between AMX/FMX and NYX shown in the NYX Teams group "Useful Information" document. Currently using a straight sampX, sampY, sampZ mapping, which has required code to use the Z axis for sample X movement in  https://github.com/NSLS-II/lsdc/pull/184

this potentially will require work on the click to center service as well.