Setup Gradle project

The pom.xml file is deleted in this patch so the patch will fail to
apply if there are changes made to it from upstream - thus notifying us
that changes were made.

paper-server/.gitignore

@@ -1,3 +1,6 @@
+.gradle/
+build/
+
 # Eclipse stuff
 /.classpath
 /.project
@@ -39,3 +42,7 @@ dependency-reduced-pom.xml
 
 /src/main/resources/achievement
 /src/main/resources/lang
+
+# vs code
+/.vscode
+/.factorypath