Exclude .github directory for export, unify wp-includes paths (#172)

Author: JanJakes

.gitattributes

@@ -5,9 +5,10 @@
 composer.json export-ignore
 phpcs.xml.dist export-ignore
 phpunit.xml.dist export-ignore
+/.github export-ignore
 /grammar-tools export-ignore
 /tests export-ignore
 /wip export-ignore
 /wp-includes/mysql export-ignore
 /wp-includes/parser export-ignore
-wp-includes/sqlite/class-wp-sqlite-crosscheck-db.php export-ignore
+/wp-includes/sqlite/class-wp-sqlite-crosscheck-db.php export-ignore