Remove IDE metadata

Don't commit intelliJ metadata to the repo.

-<?xml version="1.0" encoding="UTF-8"?>
-<module type="WEB_MODULE" version="4">
-  <component name="NewModuleRootManager" inherit-compiler-output="true">
-    <exclude-output />
-    <content url="file://$MODULE_DIR$" />
-    <orderEntry type="sourceFolder" forTests="false" />
-  </component>
-</module>
-