Update maven-checkstyle-plugin from 3.0.0 to 3.1.1.

Author: garydgregory

checkstyle.xml

@@ -55,14 +55,14 @@ limitations under the License.
     <property name="severity" value="warning" />
   </module>
 
+  <module name="LineLength">
+    <property name="max" value="120"/>
+  </module>
+
   <module name="TreeWalker">
-    <property name="cacheFile" value="target/cachefile" />
     <module name="OperatorWrap">
       <property name="option" value="eol" />
     </module>
-    <module name="LineLength">
-      <property name="max" value="120"/>
-    </module>
   </module>
 
 </module>

pom.xml

@@ -155,7 +155,7 @@
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <commons.encoding>UTF-8</commons.encoding>
 
-    <checkstyle.version>3.0.0</checkstyle.version>
+    <checkstyle.version>3.1.1</checkstyle.version>
     <checkstyle.header.file>${basedir}/LICENSE-header.txt</checkstyle.header.file>
     <checkstyle.resourceExcludes>LICENSE.txt, NOTICE.txt, **/maven-archiver/pom.properties</checkstyle.resourceExcludes>
 

src/changes/changes.xml

@@ -61,6 +61,7 @@
       <action                 type="update" dev="ggregory" due-to="Dependabot">Update actions/checkout from v1 to v2.3.1 #79.</action>
       <action                 type="update" dev="ggregory" due-to="Dependabot">Update commons-parent from 50 to 51 #80.</action>
       <action                 type="update" dev="ggregory" due-to="Dependabot">Update junit-jupiter from 5.6.1 to 5.6.2 #84.</action>
+      <action                 type="update" dev="ggregory" due-to="Gary Gregory">Update maven-checkstyle-plugin from 3.0.0 to 3.1.1.</action>
     </release>
     <release version="1.8" date="2020-02-01" description="Feature and bug fix release (Java 8).