Fixing typos and adding more details

docs/vkrt_tuto_manyhits.md.htm

@@ -185,6 +185,10 @@ void main()
 }
 ~~~~
 
+!!! Note 
+    Adding a new shader requires to rerun CMake to added to the project compilation system.
+
+
 ## `main.cpp`
 
 In `main`, after we set which hit group an instance will use, we can add the data we want to set through the shader record.