Update README and add norm calculations to vector

README.md

@@ -1,12 +1,21 @@
-# C++ Project Template
-When setting out on a new project in C++ there are a few configuration steps
-which need to be completed prior to actually getting down to writing code.
-This repository is going to be a C++ project template that already has the
-following components:
+# Vec3 
 
-- Directory Structure
-- Make Build (CMake)
-- CUDA integration
-- Unit Test Framework (Google Test)
-- API Documentation (Doxygen)
+Simple header only library defining a 3 dimensional vector type.
+
+## Installation
+
+To use from another CMake project you just need to add the following to your CMakeLists.txt:
+
+```cmake
+include(FetchContent)
+FetchContent_Declare(Vec3
+    GIT_REPOSITORY https://www.alexselimov.com/git/aselimov/Vec3.git
+)
+
+FetchContent_GetProperties(Vec3)
+if(NOT Vec3_POPULATED)
+    FetchContent_Populate(Vec3)
+    include_directories(${Vec3_SOURCE_DIR}/include)
+endif()
+```