Remove XML string writer from IOException2 message when XPath error
occurs in /api/xml request.

The XML string writer has the potential to be very large (many
megabytes or even gigabytes) and these exceptions will be logged to
the default jenkins logfile by winstone. This has the potential to
quickly use all available disk space if, for example, a jenkins poller
(i.e. a chrome extension) makes frequent calls to the API that cause
errors.

[Re-FIXED JENKINS-12457] 'Age' column on 'Test Result' tab may show incorrect value when a test suite divided into multiple junit files

Added testcase and changelog for JENKINS-13214. The actual fix is in 7fba6527

Revert "[FIXED JENKINS-12457] 'Age' column on 'Test Result' tab may show incorrect value when a test suite divided into multiple junit files"

This reverts commit 05937f53.

This provides generic consumer of ToolInstallation to expose
ToolInstallation to the build.

made sure that even if a bug similar to what was just fixed in the previous commit re-surfaces, we still won't kill the master JVM by eating its memory

Previously, a forked life cycle resulted in MavenBuildProxy2.start/end callbacks. When a module X build forks a life cycle and comes back to building module X, end callback from the fork completion made Jenkins believe that it's not building any module, when Maven is actually coming back to building module X.

So if the sequence of mojos that follow the forked mojo produces a lot of output, it can saturate memory (and even if it doesn't, Jenkins fails to capture the entire log for a module.)

This fix also addresses the synchronization problem, so that when we do split the log, we make sure all the output from Maven prior to that indeed arrived to the master.

Commented out getActions() as returns new copy of action list and thus breaks e.g. JUnitResultArchiver, which adds
actions directly to the list (build.getActions().add(action)).

Conflicts:
	changelog.html

The trick for backward compatibility is in the default implementation
that grants View.READ to those who have access to items.