remove the file generate_key_array and hash_validity_test + update README.md

Author: jvdp1

src/tests/hash_functions/README.md

@@ -1,9 +1,8 @@
-The validation directory contains code to validate the Fortran hash functions against the original C/C++ codes. It consists of three executable applications:
+The validation directory contains code to validate the Fortran hash functions against the original C/C++ codes. It consists of one executable `test_hash_functions` that:
 
-* `generate_key_array.f90` - creates a file containing 2048 random 8 bit integers.
+* creates a file containing 2048 random 8 bit integers using the subroutine
+  `generate_key_array`.
 
-* `generate_hash_arrays.cpp` - reads the file generated by `generate_key_array.f90` and uses its contents to generate 2049 hashes for each hash algorithm and outputs files containing the hashes.
+* reads the file generated by the subroutine `generate_key_array` and uses its contents to generate 2049 hashes for each C/C++ hash algorithm and outputs files containing the hashes.
 
-* `hash_validity_test.f90`- reads the file generated by `generate_key_array.f90` and uses its contents to generate 2049 hashes for each hash algorithm and compares the result with the corresponding outputs of `generate_hash_arrays.cpp` reporting if the outputs are not equal.
-
-Note the C code for nmhash assumes that the C compiler is either gcc or MSVC, and will not compile with the Intel C compiler.
+* reads the file generated by the subroutine `generate_key_array` and uses its contents to generate 2049 hashes for each Fortran hash algorithm and compares the result with the corresponding outputs of C/C++ hash algorithms.