# fod installation: can be split into 3 parts: os dependencies; virtualenv+pip dependencies; fod proper installation/setup
# exploiting docker build cache to redo only what is necessary on rebuilding of the container:
# 1) os dependencies is time and network-bandwidth consuming; normally, not to be redone quite often (os deps for FoD normally do not change, only to be redone for updating to the lates updates); will be auto redone on rebuild only if install*.sh changed
# 2) pip dependencies is still somewhat time consuming; will be auto redone on rebuild only if either install*.sh or requirements*.txt* changed
# 3) for proper installation/setup, relatively fast; will be auto redone on rebuild if anything in the FoD dir, e.g. code, changed