Rename apm-agent-java.jar to elastic-apm-agent.jar (#91)

A jar implies Java and when looking just at the JVM flags,
it's more interesting to see at a glance that this is indeed the
Elastic APM agent and not just some random Java APM agent.

apm-agent-java/pom.xml → elastic-apm-agent/pom.xml

@@ -12,7 +12,7 @@
     </parent>
     <packaging>jar</packaging>
 
-    <artifactId>apm-agent-java</artifactId>
+    <artifactId>elastic-apm-agent</artifactId>
     <name>${project.groupId}:${project.artifactId}</name>
 
     <build>

integration-tests/simple-webapp-integration-test/src/test/java/co/elastic/apm/servlet/AbstractTomcatIntegrationTest.java

@@ -75,8 +75,8 @@ public abstract class AbstractTomcatIntegrationTest {
     }
 
     private static String getPathToJavaagent() {
-        File agentBuildDir = new File("../../apm-agent-java/target/");
-        FileFilter fileFilter = new WildcardFileFilter("apm-agent-java-*.jar");
+        File agentBuildDir = new File("../../elastic-apm-agent/target/");
+        FileFilter fileFilter = new WildcardFileFilter("elastic-apm-agent-*.jar");
         for (File file : agentBuildDir.listFiles(fileFilter)) {
             if (!file.getAbsolutePath().endsWith("javadoc.jar") && !file.getAbsolutePath().endsWith("sources.jar")) {
                 return file.getAbsolutePath();

pom.xml

@@ -78,7 +78,7 @@
 
     <modules>
         <module>apm-agent-core</module>
-        <module>apm-agent-java</module>
+        <module>elastic-apm-agent</module>
         <module>apm-agent-benchmarks</module>
         <module>apm-agent-plugins</module>
         <module>apm-agent-api</module>