Added missing includes in the default SPH scheme.

src/hydro/Default/hydro.h

@@ -24,6 +24,7 @@
 #include "cosmology.h"
 #include "dimension.h"
 #include "equation_of_state.h"
+#include "hydro_properties.h"
 #include "hydro_space.h"
 #include "kernel_hydro.h"
 #include "minmax.h"

src/hydro/Default/hydro_io.h

@@ -19,6 +19,8 @@
 #ifndef SWIFT_DEFAULT_HYDRO_IO_H
 #define SWIFT_DEFAULT_HYDRO_IO_H
 
+#include "adiabatic_index.h"
+#include "hydro.h"
 #include "io_properties.h"
 #include "kernel_hydro.h"