TODO

Wed Aug 20 21:28:05 CEST 2014
ST* objects -> googleVis -> google charts: which ones?
  geochart https://google-developers.appspot.com/chart/interactive/docs/gallery/geochart : work out example of air quality aggreg per region; point to ISO 1366-1 or -2

Sort out time shift when TZ is set, or not unset, or not "" etc

Fri Apr  4 14:04:13 CEST 2014
traj <--> Tracks
move, moveStack <--> Tracks
(via STIDF?)

subsetting STF, STS, STI with [

kriging without STFDF's, kriging with STIDF's (I think this is supported now)

single location prediction.

Sat Oct 17 22:40:29 CEST 2015
Meng: coerce STIDF -> STFDF: do NOT set endTime to full interval?
  alternative: (a) zero interval width, (b) mean of endTime of each time slice?