Fix RawAndTribitsHelloWorld/README (TriBITSPub#276)

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tribits/examples/RawAndTribitsHelloWorld/README

@@ -1,14 +1,22 @@
-This is a simple raw CMake project that is used to contrast with the raw
-CMake project in ../RawHelloWorld/.
+This is a simple CMake project shows how to have a default raw CMake build
+system and secondary TriBITS build system sit side-by-side.
 
 To configure this, you just create a build dir as:
 
 $ cd $SOME_BASE_DIR
 $ mkdir BUILD
 $ cd BUILD
 
-and then configure, build, and test with:
+and then configure, build, and test with the raw CMake build system, use:
 
-$ cmake $TRIBITS_DIR/doc/example/TribitsHelloWorld
+$ cmake $TRIBITS_DIR/doc/example/RawAndTribitsHelloWorld
+$ make
+$ ctest
+
+To configure, build, and test with the TriBITS CMake build system, use:
+
+$ cmake \
+   -DRawAndTribitsHelloWorld_TRIBITS_DIR=${TRIBITS_DIR} \
+   $TRIBITS_DIR/doc/example/RawAndTribitsHelloWorld
 $ make
 $ ctest