[FIXED JENKINS-26406] Build history text field wrap fails when containing markup

[FIXED JENKINS-26718] Update changelog

JenkinsRule does the same for years.

Bump powermock to 1.5.6 that support java 8

[JENKINS-26755] cache node environment

Added test for env var expansion in SimpleBuildWrapper

to prevent inefficient channel overuse

[JENKINS-26718] OldDataMonitor: Handle poorly written project types

[FIXED JENKINS-26601] Partly reverting #1453 to avoid hitting https://github.com/google/guice/issues/899.

(cherry picked from commit 00c858d4 into 1.599 rc)

In this environment, Util.createSymlink and .isSymlink are implemented, but resolveSymlink is not.
(cherry picked from commit 388c4b5e)

Conflicts:
	changelog.html

(cherry picked from commit 75c8c31f)

(cherry picked from commit 0633beef)

JDK installer on OSX

Make WorkspaceList.Lease implement AutoCloseable for Java 7 callers, to make releasing the lease more convenient.

[JENKINS-26698] Make sure BuildExecution.cleanUp always calls super, to release the workspace lease.
Also stop closing the build log in Run.handleFatalBuildProblem; we want to see any subsequent messages too.

In this environment, Util.createSymlink and .isSymlink are implemented, but resolveSymlink is not.

Note some nonnull parameters

[JENKINS-26643] DescribableList.buildDependencyGraph should catch RuntimeException

Add extra info if the slave can not restart correctly.

If the service can not reliably restart itself add link to the wiki with
some information about how to fix it.

[FIXED JENKINS-26601] Partly reverting #1453 to avoid hitting https://github.com/google/guice/issues/899.

Trying to diagnose hung connection in UC download.

Observed in 1.580.1 on credentials-plugin (which you would think would be tiny and fast to get):
"Update center installer thread [#1]" #70 daemon prio=5 os_prio=0 tid=0x00007f5634815800 nid=0x64a8 runnable [0x00007f567cfe4000]
   java.lang.Thread.State: RUNNABLE
	at java.net.SocketInputStream.socketRead0(Native Method)
	at java.net.SocketInputStream.read(SocketInputStream.java:150)
	at java.net.SocketInputStream.read(SocketInputStream.java:121)
	at java.io.BufferedInputStream.read1(BufferedInputStream.java:284)
	at java.io.BufferedInputStream.read(BufferedInputStream.java:345)
	- locked <0x00000007aa3ec760> (a java.io.BufferedInputStream)
	at sun.net.www.MeteredStream.read(MeteredStream.java:134)
	- locked <0x00000007aa3eedd8> (a sun.net.www.MeteredStream)
	at java.io.FilterInputStream.read(FilterInputStream.java:133)
	at sun.net.www.protocol.http.HttpURLConnection$HttpInputStream.read(HttpURLConnection.java:3322)
	at sun.net.www.protocol.http.HttpURLConnection$HttpInputStream.read(HttpURLConnection.java:3315)
	at org.apache.commons.io.input.ProxyInputStream.read(ProxyInputStream.java:77)
	at hudson.model.UpdateCenter$UpdateCenterConfiguration.download(UpdateCenter.java:766)
	at hudson.model.UpdateCenter$DownloadJob._run(UpdateCenter.java:1138)
	at hudson.model.UpdateCenter$InstallationJob._run(UpdateCenter.java:1298)
	at hudson.model.UpdateCenter$DownloadJob.run(UpdateCenter.java:1116)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at hudson.remoting.AtmostOneThreadExecutor$Worker.run(AtmostOneThreadExecutor.java:104)
	at java.lang.Thread.run(Thread.java:745)