Add Michael Bull's Maven repository

https://github.com/michaelbull/kotlin-inline-logger is not in the
central repository.

pom.xml

@@ -71,6 +71,17 @@
   </dependencyManagement>
 
   <repositories>
+    <repository>
+      <id>michaelbull</id>
+      <name>Michael Bull</name>
+      <url>https://dl.bintray.com/michaelbull/maven/</url>
+      <releases>
+        <enabled>true</enabled>
+      </releases>
+      <snapshots>
+        <enabled>false</enabled>
+      </snapshots>
+    </repository>
     <repository>
       <id>openrs2</id>
       <name>OpenRS2</name>