Updates build versions

.mvn/wrapper/maven-wrapper.properties

@@ -1 +1 @@
-distributionUrl=https://repo1.maven.org/maven2/org/apache/maven/apache-maven/3.3.3/apache-maven-3.3.3-bin.zip
+distributionUrl=https://repo1.maven.org/maven2/org/apache/maven/apache-maven/3.3.9/apache-maven-3.3.9-bin.zip

README.md

@@ -5,7 +5,7 @@ Experimental java zipkin backend. Please look at issues as we are currently work
 You can run the experimental server to power the zipkin web UI.
 
 ```bash
-$ (cd zipkin-java-server; mvn spring-boot:run)
+$ ./mvnw -pl zipkin-java-server spring-boot:run
 ```
 
 ### Docker  

pom.xml

@@ -44,11 +44,11 @@
 
          MariaDB has a friendlier license, LGPL, which is less scary in audits.
     -->
-    <mariadb-java-client.version>1.3.0</mariadb-java-client.version>
+    <mariadb-java-client.version>1.3.2</mariadb-java-client.version>
     <junit.version>4.12</junit.version>
     <assertj.version>3.2.0</assertj.version>
 
-    <maven-plugin.version>0.3.1</maven-plugin.version>
+    <maven-plugin.version>0.3.3</maven-plugin.version>
     <maven-install-plugin.version>2.5.2</maven-install-plugin.version>
     <maven-source-plugin.version>2.4</maven-source-plugin.version>
     <maven-javadoc-plugin.version>2.10.3</maven-javadoc-plugin.version>
@@ -191,7 +191,7 @@
   <build>
     <pluginManagement>
       <plugins>
-        <!-- mvn -N io.takari:maven:wrapper -Dmaven=3.3.3 -->
+        <!-- mvn -N io.takari:maven:wrapper -Dmaven=3.3.9 -->
         <plugin>
           <groupId>io.takari</groupId>
           <artifactId>maven</artifactId>