[FIXED JENKINS-25074] Make sure to call Job.getBuildHealthReports just once per t:buildHealth render.
(cherry picked from commit f463abbe53488747725ea2e45dfc4a98ada02b8e)

Conflicts:
	changelog.html
[FIXED JENKINS-25473] move config file check as part of loading job to do it in multithread fashion than in a single thread

(cherry picked from commit dc547cf2974365a6b355de9981b7183f3d4fc17f)
[JENKINS-25144]

return authentication object instead of null if authentication is not
required - otherwise valid login fails with basic authentication

(cherry picked from commit 0176b6d902faeec7bff63eb34ce16e2f70062035)
[FIXED JENKINS-25144] Revisiting the attempted fix in the previous commit.

IIUC, the issue here is that the request in question contains both a
valid session cookie AND basic authentication header, and that path
results in a failure because BasicHeaderProcessor expects one of
BasicHeaderAuthenticators to validate the basic authentication header
(without knowing that there's already a valid Authentication object that
came from the HTTP session, yet no BasicHeaderAuthenticator actually
processes this because BasicHeaderRealPasswordAuthenticator backs away
from doing that.

I think the corect fix is for BasicHeaderRealPasswordAuthenticator to
get rid of authenticationIsRequired check. This check instead belongs to
BasicHeaderProcessor, where it should be used to check if any
BasicHeaderAuthenticator should be consulted or not.

The problem with having this logic in
BasicHeaderRealPasswordAuthenticator is that this is just an
implementation of an extension point, and thus it needs to be removable.
As it stands right now in this fix, if this impl is removed,
JENKINS-25144 will be back again.

(cherry picked from commit 9e81b8e4feebceef94d117b757952c965bf91c61)
[FIXED JENKINS-25655] Incorrect caching from entrySet sometimes caused incorrect results.
Caused a failure in hudson.plugins.promoted_builds.conditions.ManualConditionTest.testManualPromotionProcessViaWebClient when run against 1.580.1.
(cherry picked from commit b76e7bf9988ebf5b3b7e2c5e588d5ce6dbde957e)
[FIXED JENKINS-25759] Avoid consuming too much memory while running validateAntFileMask.
Not fully solved, since the scannedDirs field can still grow to be large, but at least clearing files/dirsNotIncluded.
Also imposing a 5s timeout on the scan regardless of file count, and defining a user-customizable bound.
(cherry picked from commit 534328b264f9338e48418d2bcc0d28daaf48b3a0)

Conflicts:
	changelog.html