Update fluids/README and fluids/index.rst for with path

Author: valeriabarra

examples/fluids/README.md

@@ -12,6 +12,8 @@ with different problem definitions according to the application of interest.
 
 Build by using
 
+`cd navier-stokes`
+
 `make`
 
 and run with
@@ -264,6 +266,8 @@ The main shallow-water solver for libCEED is defined in [`shallowwater.c`](shall
 
 Build by using
 
+`cd shallow-water`
+
 `make`
 
 and run with

examples/fluids/index.rst

@@ -3,7 +3,7 @@
 Compressible Navier-Stokes mini-app
 ========================================
 
-This example is located in the subdirectory :file:`examples/fluids`. It solves
+This example is located in the subdirectory :file:`examples/fluids/navier-stokes`. It solves
 the time-dependent Navier-Stokes equations of compressible gas dynamics in a static
 Eulerian three-dimensional frame using unstructured high-order finite/spectral
 element spatial discretizations and explicit high-order time-stepping (available in