added instructions on how to run tests

README.md

@@ -53,4 +53,15 @@ typedef struct {
   int16_t y;
   int32_t data[9];
 } Cluster ;
+```
+
+## Running tests
+
+```bash
+#Tell the program where the test data is located. 
+# Can change depending on how you mounted sls_det_storage
+$ export CREADER_TEST_DATA=/mnt/sls_det_storage/moench_data/cluster_reader_test/
+
+$ make test
+
 ```