added plugin version + encoding to silence warnings (#195)

Author: elijulian

pom.xml

@@ -104,7 +104,9 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.10.1</version>
                 <configuration>
+                    <encoding>UTF-8</encoding>
                     <source>8</source>
                     <target>8</target>
                 </configuration>