related to #7
one more MediaTestModel
related to #7

use density_ph_state to remove input phase and instead add input state
this seems to work, more testing needed
when using fluid connectors, p and h are usually the preferred states
typo
new Type DerTemperatureByEnthalpy
rewrite density_pT and temperature_ph to use intermediate functions with state input,

new functions density_pT_der and temperature_ph_der,
new functions temperature_derp_h and temperature_derh_p
Full path
add annotation Inline=true
comment input FixedPhase.

further testing needed: is it really necessary to remove the phase and add the state?
or is it all about Inline and LateInline ??
related to #7
this way index reduction still works, but simulation time is longer due to repeated calls of setState_ph
Revert "this way index reduction still works, but simulation time is longer due to repeated calls of setState_ph"

This reverts commit 7cb3d3e5466191037a4f415e5d6ade228e36f61a.