Begin to implement EOS
More EOS implementation! and really useful commit descriptions
Compiles!
q
sry for doublecommit
Some more stuff, rm of binary blob
Adapt canonical module structure
Establish and extend Fluid trait

This separation works out a Fluid trait that can be used for different
equations of state. It is implemented by a concrete type using an adiabatic
equation of state with an ideal gas and primitive variables as backend.
Move test into separate module

Thereby some privacy issues have been fixed.
Merge pull request #1 from aepsil0n/EOS

Draft for handling different types of fluids