TOMEE-2444 Enable language support for examples

[cesarhernandezgt]

No description provided.

[cesarhernandezgt]

To review this PR you need:

1. build the project: tomee-site-generator$ mvn clean install
2. Choose any example like for example tomee-site-generator/repos/tomee-8.0/examples/mp-config-example/ and create a readme file with a suffix that represents the translation for the readme. For example: README_fr.adoc.
3. Build and run the project: tomee-site-generator$ mvn clean compile -Djbake.http=true
4. The project should show in http://localhost:8080/docs.html the [fr] link to the examples in french.

[brunobat]

My build fails:

Tests in error:
testProcess(org.apache.tomee.website.GroupedIndexTest): java.io.FileNotFoundException: /tmp/temp5520959884794493991dir/en/examples/index.html (No such file or directory)

Tests run: 9, Failures: 0, Errors: 1, Skipped: 0

[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------

Master looks ok.

[brunobat]

With mvn clean install
Build is ok now.
We have an exception close to the end, but it's not harming the result:

[WARNING] Couldn't destroy threadgroup org.codehaus.mojo.exec.ExecJavaMojo$IsolatedThreadGroup[name=org.apache.tomee.website.JBake,maxpri=10]
java.lang.IllegalThreadStateException
at java.lang.ThreadGroup.destroy (ThreadGroup.java:778)
at org.codehaus.mojo.exec.ExecJavaMojo.execute (ExecJavaMojo.java:321)
at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo (DefaultBuildPluginManager.java:137)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:210)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:156)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:148)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:117)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:81)
at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build (SingleThreadedBuilder.java:56)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:128)
at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:305)
at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:192)
at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:105)
at org.apache.maven.cli.MavenCli.execute (MavenCli.java:956)
at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:288)
at org.apache.maven.cli.MavenCli.main (MavenCli.java:192)
at sun.reflect.NativeMethodAccessorImpl.invoke0 (Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke (NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke (DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke (Method.java:498)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:289)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:229)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:415)
at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:356)