Add Guava and SLF4J dependencies to the util module

Almost everything will depend on these, so it is easiest to pull them in
via util rather than repeating the dependencies several times.

util/pom.xml

@@ -12,4 +12,15 @@
   <packaging>jar</packaging>
 
   <name>OpenRS2 Utilities</name>
+
+  <dependencies>
+    <dependency>
+      <groupId>com.google.guava</groupId>
+      <artifactId>guava</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-api</artifactId>
+    </dependency>
+  </dependencies>
 </project>