[Users] EOS_Omni

[Christian D. Ott]

Dear All,

 you can give the new EOS for GRHydro a try by recompiling with
 -DUSE_EOS_OMNI in CPPFLAGS and FPPFLAGS.
 This makes GRHydro _independent_ of EOS_Base and all EOS thorns except
 EOS_Omni (dependence via aliased functions).

 Let's say you want to evolve a Gamma=2 polytrope with K=100 with a gamma-law.
 For this, you would set:
 
 ActiveThorns = "EOS_Omni"

 grhydro::grhydro_poly_eoskey = 1
 grhydro::grhydro_eoskey = 2
 eos_omni::gl_gamma = 2.0
 eos_omni::gl_k = 100.0d0
 eos_omni::poly_gamma = 2.0
 eos_omni::poly_gamma_ini = 2.0
 eos_omni::poly_k = 100.0d0

 Note that gl_ controls the gamma-law settings and that
 poly settings are still needed (for fallback purposes in GRHydro if c2p fails).

 Without the preprocessor defines, the code behaves as usual and is wedded to
 EOS_Base and EOS_Polytrope. All test suites pass. A test suite using EOS_Omni
 has been added. If EOS_Omni is activated and EOS_Omni parameters are added, all
 standard testsuites pass. This confirms that EOS_Omni produces the same results
 as EOS_Base + EOS_Polytrope/EOS_Ideal_Fluid/EOS_Hybrid.

 Currently, finite-temperature EOS support is lacking. This requires messing with
 various routines in GRHydro to include temperature in calls etc. This will be 
 the next step in the EOS_Omni development.

 Since EOS_Omni already provides the entire functionality of the EOS_Base
 interface, I would suggest to remove this old interface from the code soon (once
 people have tried out and are happy with EOS_Omni).

 Please report any problems you may find with EOS_Omni.

Best,

 - Christian