[FIXED JENKINS-38473] Set a short timeout on the socket when using it to wake the acceptor thread. (#2564)

* [FIXED JENKINS-38473] Set a short timeout on the socket when using it to wake the acceptor thread.

* [JENKINS-38473] Remove leftover typing in wrong window

Diff: https://github.com/jenkinsci/extras-executable-war/compare/executable-war-1.33...executable-war-1.34

* https://issues.jenkins-ci.org/browse/JENKINS-23232
* https://issues.jenkins-ci.org/browse/JENKINS-34287

[FIX JENKINS-38187] Fix setting JNLP port through system property

[FIXED JENKINS-38534] Isolate the code that requires the `Jenkins` class to be loaded from an agent code path

[FIXED JENKINS-38534] Isolate the code that requires the `Jenkins` class to be loaded from an agent code path

Enhance tests of jenkins.util.SystemProperties

Serbian [sr] translation of properties files

Remove the broken packaging testing temporarily

[FIX JENKINS-38391] Show admin monitors on most URLs

* [FIX JENKINS-18114] Exclude /cli URL from crumb requirement

* [JENKINS-18114] Fix test: Don't send the crumb

The CLI doesn't do this either.

[JENKINS-32148] - Add :hover to all stripped table rows

- Add tooltip to notification button
- Move CSS/JS into an adjunct
- Check adcitve admin monitors status last
- Don't show on /configure URL

This code can come back, IMO, after @svanoort and I fix the unpleasant/broken
tight-coupling between this Jenkinsfile and Groovy code floating around in the
jenkinsci/packaging repository

This needs to be reworked a bit to accomodate more modern versions of Jenkins
Pipeline

Fix setting up slave agent port through -Djenkins.model.Jenkins.slaveAgentPort on startup.
Add -Djenkins.model.Jenkins.slaveAgentPortEnforce=true to enforce slave agent port on every start,  and an administrative monitor in case the value is modified through UI.

* [JENKINS-35184] Servlet API dependent bits in a inner-class

This is in order to avoid loading ServletContextListener class
from slaves classloader.

* [JENKINS-35184] Don't use SystemProperties while initializing remote agents

This rolls back the previous commit and introduces a new way to construct
RingBufferLogHandler which avoids relying on SystemProperties to get the
default size.

* [JENKINS-35184] Mark SystemProperties as OnMaster only class

Adding `OnMaster` annotation does not prevent the class from being
loaded on remote agent but it gives a hint that this class should not
be used on a remote agent.

* [JENKINS-35184] Set SLAVE_LOG_HANDLER at the very beginning

In the previous code cleaning existing log handlers, SLAVE_LOG_HANDLER
is always null, as static fields are scoped by classloader.

Present stacktrace when throwable attached to Descriptor.FormException

[FIX JENKINS-38301] Add configuration for disabling admin monitors