Add .gitattributes file

.gitattributes

@@ -0,0 +1,13 @@
+# Exclude these files from release archives.
+# This will also make them unavailable when using Composer with `--prefer-dist`.
+# If you develop for this package using Composer, use `--prefer-source`.
+# https://www.reddit.com/r/PHP/comments/2jzp6k/i_dont_need_your_tests_in_my_production
+# https://blog.madewithlove.be/post/gitattributes/
+
+/.editorconfig       export-ignore
+/.gitattributes      export-ignore
+/.gitignore          export-ignore
+/.phpcs.xml.dist     export-ignore
+/CHANGELOG.md        export-ignore
+/CODE_OF_CONDUCT.md  export-ignore
+/README.md           export-ignore