Added a second top level class in Greeting.java

This reproduces an issue we're seeing in some code with a package protected class at the top level in the same file with another top level class.   I don't know why they did it this way, but apparently it is valid and Maven handles it.   In Pants, it compiles with a warning:

```
17:21:56 00:00           [scan_deps]
                       Missing BUILD dependency src/java/com/pants/examples/hello/greet -> .pants.d/compile/java/classes/com/pants/examples/hello/greet/EnglishGreeting.class
```

But it fails to bundle the .class file into a .jar file.

```
java -jar dist/main-bundle/main-bin.jar 
log4j:ERROR Could not read configuration file [log4j.properties].
java.io.FileNotFoundException: log4j.properties (No such file or directory)
	at java.io.FileInputStream.open(Native Method)
	at java.io.FileInputStream.<init>(FileInputStream.java:131)
	at java.io.FileInputStream.<init>(FileInputStream.java:87)
	at org.apache.log4j.PropertyConfigurator.doConfigure(PropertyConfigurator.java:316)
	at org.apache.log4j.PropertyConfigurator.configure(PropertyConfigurator.java:342)
	at com.pants.examples.hello.main.HelloMain.main(HelloMain.java:15)
log4j:ERROR Ignoring configuration file [log4j.properties].
Exception in thread "main" java.lang.NoClassDefFoundError: com/pants/examples/hello/greet/EnglishGreeting
	at com.pants.examples.hello.greet.Greeting.greet(Greeting.java:8)
	at com.pants.examples.hello.main.HelloMain.main(HelloMain.java:16)
Caused by: java.lang.ClassNotFoundException: com.pants.examples.hello.greet.EnglishGreeting
	at java.net.URLClassLoader$1.run(URLClassLoader.java:372)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:360)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	... 2 more
```

We are working around the issue by just putting each class into its own file.