Add pt-BR translation in usage statistics

Fix some typos in Usage Statistics Help pages (en & fr)

[JENKINS-33971] ReverseBuildTrigger.upstream2Trigger cache fix

Also switching to the closure-based method which is not susceptible to bad nesting mistakes.

[FIXED JENKINS-33971] ReverseBuildTrigger.upstream2Trigger was not being reliably calculated during Jenkins startup.

And don't fail if no version can be found.

[JENKINS-33826] build history badges styling issues

Use rerunFailingTestsCount rather than @RandomlyFails

* Check that dependencies are enabled. A disabled optional dependency
  will not prevent a plugin from loading.
* Check versions of dependencies declared by a plugin before loading it.
  If any dependency (even optional) is older than what is required,
  then the plugin isn't loaded.

This should prevent use cases where a plugin is loaded but one of its
dependencies is too old so that :
* its @Extension annotated classes cannot be loaded, causing the full
  Jenkins to blow up with crapload of exceptions which are tedious to
  investigate to understand the root cause.
* NoSuchMethodError and the likes at runtime even though boot has
  completed.

Version check (for setups where version list is manually crafted but yet
works) can be disabled by starting Jenkins with

-Dhudson.PluginWrapper.dependenciesVersionCheck.enabled=true

Minor fixes done while implementing this change :
* Fix version parsing in PluginWrapper.Dependency
* Dynamic plugin load didn't check for disabled flag

Fix advertised JNLP Port

As far as I can figure, the /TcpSlaveAgentListener/ endpoint headers
tell the slaves what the JNLP port is. When I'm running jenkins behind a
proxy (marathon using the mesos plugin, which bridged networking), even
though I was setting the advertised port per a thread[1], it was not
accurately being returned in the header. This patch fixes that.

[1] https://groups.google.com/d/topic/jenkins-mesos/qUrXpDY07TQ/discussion

initializer annotation on instance methods

... which is done by looking for locating & instantiating ExtensionFinders.

This simplifies typical usage of them.

... or else it'll keep running. This can be seen as a large number of zombie threads like the following in the unit test:

"NioChannelHub keys=0 gen=0: Computer.threadPoolForRemoting [#250]" daemon prio=10 tid=0x00007f793d841000 nid=0x3cc1 runnable [0x00007f78e2665000]
   java.lang.Thread.State: RUNNABLE
        at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
        at sun.nio.ch.EPollArrayWrapper.poll(EPollArrayWrapper.java:228)
        at sun.nio.ch.EPollSelectorImpl.doSelect(EPollSelectorImpl.java:81)
        at sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:87)
        - locked <0x00000000c50d46d8> (a sun.nio.ch.Util$2)
        - locked <0x00000000c50d46e8> (a java.util.Collections$UnmodifiableSet)
        - locked <0x00000000c50d4690> (a sun.nio.ch.EPollSelectorImpl)
        at sun.nio.ch.SelectorImpl.select(SelectorImpl.java:98)
        at sun.nio.ch.SelectorImpl.select(SelectorImpl.java:102)
        at org.jenkinsci.remoting.nio.NioChannelHub.run(NioChannelHub.java:542)
        at jenkins.util.ContextResettingExecutorService$1.run(ContextResettingExecutorService.java:28)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
        at java.util.concurrent.FutureTask.run(FutureTask.java:166)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:722)

Be quiet