applications/solvers/modules: Reorganised to match the structure of tutorials/modules

Given that the number of solid solver modules is currently 1 and unlikely to
exceed 3 it is not very useful to maintain solid and fluid sub-directories and
easier to see the correspondence between the solver modules and tutorial cases
without.

applications/solvers/modules/fluidSolver/Make/files

@@ -0,0 +1,3 @@
+fluidSolver.C
+
+LIB = $(FOAM_LIBBIN)/libfluidSolver

applications/solvers/modules/fluidSolver/Make/options

@@ -0,0 +1,16 @@
+EXE_INC = \
+    -I$(LIB_SRC)/MomentumTransportModels/momentumTransportModels/lnInclude \
+    -I$(LIB_SRC)/MomentumTransportModels/incompressible/lnInclude \
+    -I$(LIB_SRC)/physicalProperties/lnInclude \
+    -I$(LIB_SRC)/finiteVolume/lnInclude \
+    -I$(LIB_SRC)/meshTools/lnInclude
+
+LIB_LIBS = \
+    -lmomentumTransportModels \
+    -lincompressibleMomentumTransportModels \
+    -lphysicalProperties \
+    -lfiniteVolume \
+    -lfvModels \
+    -lfvConstraints \
+    -lsampling \
+    -lmeshTools