Added git export ignores

This should help generate clean production tarballs from git.

.gitattributes

@@ -31,3 +31,22 @@
 *.frm binary
 *.MYD binary
 *.MYI binary
+
+# Export ignores to generate clean production tarballs
+/build              export-ignore
+/dev                export-ignore
+/doc                export-ignore
+/test               export-ignore
+.buildpath          export-ignore
+/build.xml          export-ignore
+.codeclimate.yml    export-ignore
+Dockerfile          export-ignore
+.dockerignore       export-ignore
+.editorconfig       export-ignore
+.gitattributes      export-ignore
+.gitignore          export-ignore
+.mailmap            export-ignore
+.scrutinizer.yml    export-ignore
+.settings           export-ignore
+.travis.yml         export-ignore
+.tx                 export-ignore