feat(config): add readme and clean up dir

lua/cosmic/config/examples/readme.md

@@ -0,0 +1,20 @@
+## Configuration
+
+There are four main configuraiton files that you may want to create.
+
+- cosmic/config/config.lua
+- cosmic/config/editor.lua
+- cosmic/config/mappings.lua
+- cosmic/config/plugins.lua
+
+Please look at the examples in this directory in order to get started.
+
+#### Quick Start
+
+```
+# from project root
+cp ./lua/cosmic/config/examples/config.lua ./lua/cosmic/config/config.lua
+cp ./lua/cosmic/config/examples/editor.lua ./lua/cosmic/config/editor.lua
+cp ./lua/cosmic/config/examples/mappings.lua ./lua/cosmic/config/mappings.lua
+cp ./lua/cosmic/config/examples/plugins.lua ./lua/cosmic/config/plugins.lua
+```