note vendored libraries

vendor/README.md

+# Vendor Libraries
+This folder contains 3rd party code we need to ship with our build.
+Compile-time only dependencies, or dependencies which can be included using cmake directly will not be included within this folder.
+
+| Library    | Purpose                                          | Licence |
+|------------|--------------------------------------------------|---------|
+| GLAD       | Allow loading of OpenGL libraries and extentions | MIT     |
+| Dear IMGUI | Debugging UI/Editor windows                      | MIT     |
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