Remove GWT support.

Also target source 1.9 as we no longer need 1.8 for GWT and hopefully the rest
of the world has moved on from Java 1.8 in the last twenty years.

pom.xml

@@ -41,32 +41,16 @@
     <url>http://github.com/samskivert/jmustache</url>
   </scm>
 
-  <!-- we only uncomment this when checking for plugin updates, due to Maven inanity
   <prerequisites>
-    <maven>3.3.0</maven>
+    <maven>3.9.2</maven>
   </prerequisites>
-  -->
 
   <properties>
-    <source.level>1.8</source.level>
+    <source.level>1.9</source.level>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <gwt.version>2.8.2</gwt.version>
-    <gwt.maven.version>2.8.2</gwt.maven.version>
   </properties>
 
   <dependencies>
-    <dependency>
-      <groupId>com.google.gwt</groupId>
-      <artifactId>gwt-dev</artifactId>
-      <version>${gwt.version}</version>
-      <scope>test</scope>
-    </dependency>
-    <dependency>
-      <groupId>com.google.gwt</groupId>
-      <artifactId>gwt-user</artifactId>
-      <version>${gwt.version}</version>
-      <scope>test</scope>
-    </dependency>
     <dependency>
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>
@@ -82,20 +66,6 @@
   </dependencies>
 
   <build>
-    <resources>
-      <!-- include the source files in our main jar for use by GWT -->
-      <resource>
-        <directory>${project.build.sourceDirectory}</directory>
-        <excludes>
-          <exclude>com/samskivert/mustache/DefaultCollector.java</exclude>
-        </excludes>
-      </resource>
-      <!-- also include the GWT-specific sources -->
-      <resource>
-        <directory>src/main/gwt</directory>
-      </resource>
-    </resources>
-
     <plugins>
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
@@ -104,8 +74,6 @@
         <configuration>
           <source>${source.level}</source>
           <target>${source.level}</target>
-          <testSource>1.8</testSource>
-          <testTarget>1.8</testTarget>
           <fork>true</fork>
           <showDeprecation>true</showDeprecation>
           <showWarnings>true</showWarnings>
@@ -145,7 +113,7 @@
       <plugin>
         <groupId>org.apache.felix</groupId>
         <artifactId>maven-bundle-plugin</artifactId>
-        <version>4.2.0</version>
+        <version>5.1.1</version>
         <extensions>true</extensions>
         <configuration>
           <instructions>
@@ -157,22 +125,6 @@
         </configuration>
       </plugin>
 
-      <plugin>
-        <groupId>org.codehaus.mojo</groupId>
-        <artifactId>gwt-maven-plugin</artifactId>
-        <version>${gwt.maven.version}</version>
-        <executions>
-          <execution>
-            <goals>
-              <goal>test</goal>
-            </goals>
-          </execution>
-        </executions>
-        <configuration>
-          <mode>htmlunit</mode>
-        </configuration>
-      </plugin>
-
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-resources-plugin</artifactId>

src/test/java/com/samskivert/mustache/SharedTests.java

@@ -10,21 +10,16 @@
 import java.io.Writer;
 import java.util.*;
 
-import com.google.gwt.junit.client.GWTTestCase;
-
 import org.junit.Test;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
 /**
- * Unit tests that can be shared between GWT and the JVM. Put GWT-only tests in
- * {@code GwtTestMustache.java} and JVM-only tests in {@code MustacheTest.java}.
+ * Vestige from when JMustache supported both GWT and JVM.
  */
-public abstract class SharedTests extends GWTTestCase
+public abstract class SharedTests
 {
-    @Override public String getModuleName () { return null; }
-
     @Test public void testSimpleVariable () {
         test("bar", "{{foo}}", context("foo", "bar"));
     }