Provcide more flexiblity in using HIP_PATH to control installation.

Also improve docs for developers / contributing.

tests/README.md

@@ -1,6 +1,9 @@
-Tests uses CMAKE as teh build infrastructure.
+# HIP testing environment.
 
-Use :
+This document explains how to use the HIP CMAKE testing environment.  
+
+### Quickstart
+Usage :
 ```
 $ mkdir build
 $ cd build
@@ -9,31 +12,29 @@ $ make
 $ make test
 ```
 
-#-----
 ### How to add a new test
 
-edit src/CMakeFiles to add the test:
+The tests/src/hipMemtest.cpp file contains a simple unit test and is a good starting point for other tests.  
+Copy this to a new test name and modify tests/src/CMakefiles.txt to add the test to the build environment.
 
-### add the executable and list of required CPP files, ie:
+#### Edit CMakefiles.txt:
+// Example:
 ```
-make_test (EXE CPP_FILES)
-make_hip_executable (hipMemset hipMemset.cpp)
-```
-
-### Add to automated Test framework:
-```
-make_test (TESTNAME ARGS)
+make_hip_executable (hipMemset hipMemset.cpp) 
 make_test(hipMemset " ")
 ```
 
-
 ### Running tests:
 ```
-make test
+ctest
 ```
 
-# Run a specific test:
+### Run subsets of all tests:
 ```
+# Run one test on the commandline (obtain commandline parms from CMakefiles.tst)
 ./hipMemset
+
+# Run all the memory tests:
+ctest -R Memcpy
 ```