post process pos

adapt main pos plotting and ratemap to use xy data buffer rather than
raw buffer. Also convert pixels to mm, change nans and add nans for
jumpy.
pos plot sizing
pos process interp and smooth
feature - settable pos processing params

using  T.ORG.SetPos* on command line
Note no dedicated living in T.ORG yet.
improve - smoothing algo is less naive
feature - ui for pos params
bugfix - pos params localstorage
improve - living for pos