Added .gitattributes file

.gitattributes

@@ -0,0 +1,15 @@
+# Path-based git attributes
+# https://www.kernel.org/pub/software/scm/git/docs/gitattributes.html
+
+# This way, the files would be available in the repository but it would not be downloaded when the package is required by another project.
+/.editorconfig      export-ignore
+/.gitattributes     export-ignore
+/.gitignore         export-ignore
+/.travis.yml        export-ignore
+/CHANGELOG.md       export-ignore
+/CODE_OF_CONDUCT.md export-ignore
+/CONTRIBUTING.md    export-ignore
+/README.md          export-ignore
+/phpunit.xml        export-ignore
+/screenshot.png     export-ignore
+/tests              export-ignore