Add RAJA build instructions to README

Author: tomdeakin

README.md

@@ -48,6 +48,14 @@ For building with CUDA support, we use the following command, specifying the `ar
 ../generate_makefile.bash --prefix=<prefix> --with-cuda --with-openmp --with-pthread --arch=<arch> --with-cuda-options=enable_lambda
 ```
 
+Building RAJA
+-------------
+
+We use the following command to build RAJA using the Intel Compiler.
+```
+cmake ../../ -DCMAKE_INSTALL_PREFIX=<prefix> -DCMAKE_C_COMPILER=icc -DCMAKE_CXX_COMPILER=icpc -DRAJA_PTR="RAJA_USE_RESTRICT_ALIGNED_PTR" -DCMAKE_BUILD_TYPE=ICCBuild -DRAJA_ENABLE_TESTS=Off
+```
+
 
 Results
 -------