[FIXED JENKINS-23094] Use POST to start slave agent

[FIXED JENKINS-23361] Add CLI commands to add jobs to and remove jobs from views

Plugins like github-oauth-plugin implementing SecurityRealm need to call
these methods in security lifecycle events.

[JENKINS-21631] - Don't fail with NPE if the PeepholePermalink cache contains the non-numeric value.

Actually, the change just prevents symptoms. There should be an error somewhere else.
Signed-off-by: NOleg Nenashev <o.v.nenashev@gmail.com>

Integrated the fix made in winp 1.20.

Link to 'Building Jenkins' page from text file

MockFolderTest.moving pointed out a refinement to 1197e0ce: list folders, if included, before their contents.

Signed-off-by: NOleg Nenashev <o.v.nenashev@gmail.com>

Move entries older than last year to changelog-old

Cf.: https://github.com/jenkinsci/metrics-plugin/commit/b7a2f58c977c8d1053d702e36dcc36bb1348e1aa

Improved robustness of RunParameterValue so it does not break the REST API when there is invalid data.
Observed in 1.554.1:
java.lang.ArrayIndexOutOfBoundsException: 1
        at hudson.model.RunParameterValue.getNumber(RunParameterValue.java:63)

Fix translation error

[JENKINS-23365] Follow-up API fixes: introduce SCM.getKey(), and add an SCMRevisionState baseline argument to checkout.
Necessary in order to produce correct changelogs by SCM plugins which actually use SCMRevisionState correctly (unlike git-plugin!).
(cherry picked from commit df9dc4c8)

(cherry picked from commit abf33593)

[JENKINS-23365] Follow-up API fixes: introduce SCM.getKey(), and add an SCMRevisionState baseline argument to checkout.
Necessary in order to produce correct changelogs by SCM plugins which actually use SCMRevisionState correctly (unlike git-plugin!).