GEAR : add a new flag JEANS_PRESSURE_FLOOR that allow to use a pressure floor in order to avoid the gas fragmentation. NOTE: the energy is no longer conserved.

GEAR : in hydra, in the viscosity routines, add:

if (SphP[j].DeltaEgySpec>0)
which avoids to update the sound speed when no feedback
is used. This avoids the strong timestep decrease.