CAS code can be accessed from Excel, DTU env. data to be converted to a JSON dictionary directly

Signed-off-by: Ian Bell <ian.h.bell@gmail.com>
Use SI units for hmax

Signed-off-by: Ian Bell <ian.h.bell@gmail.com>
Added file with ASHRAE 34 fluids and CAS numbers

Signed-off-by: Ian Bell <ian.h.bell@gmail.com>
Fixes to ASHRAE34 information

Signed-off-by: Ian Bell <ian.h.bell@gmail.com>
Fixed bug with REFPROP mixtures mole fractions not being cached properly between calls

Signed-off-by: Ian Bell <ian.h.bell@gmail.com>
Merge branch 'master' of https://github.com/ibell/coolprop
Fixed Python build script for py3.x

Signed-off-by: Ian Bell <ian.h.bell@gmail.com>