JNA 4.1.0 has a proper license, so remove workaround in
licenseCompleter.groovy. [JENKINS-24521]

Integrated the trilead with SecureRandom instantiation fix.

This version includes a change from christ66 in
https://github.com/stapler/stapler/pull/40

Bumping up dependencies to 1.3.1, with extra precaution to make
DiskFileItem non-serializable

The primary change is that the thread name update code now lives in a
filter instead of 'Stapler' servlet, so it happens a lot earlier.

This version checks the critical flag of the process, as killing such a
process results in BSoD.

[JENKINS-19192] Using JNR 3.0.1 which includes JNR-FFI 1.0.7; 1.0.6 has the backported fix for Guava #1505, the root cause.
So this upgrade ought to prevent a recurrence of the issue in case some other code refers to JNR from the CLI.
(As yet untested, and we do not especially want to send JNR over the CLI channel anyway for performance reasons.)

Stapler 1.218.1 was apparently never even deployed to the Maven repo, so let us just skip straight to 1.229 which has the fix and which we are using in the merged release branches anyway.

Added "X-Content-Type-Options: nosniff" for serving user-generated
contents to improve security a little bit

ZeroClipboard 1.3.5 is rather incompatible with 1.1.7, and various API changes were needed.

 - setText() call doesn't work until the DOM is populated, which is at some unknown time AFAICT.
   installing it via the datarequested event avoids this problem.
 - constructor now demands the element to attach to, and it's unclear if relative positioning is working or not.
 - "display: inline-block" is needed for ZeroClipboard to correctly compute the height of the element

Integrating dom4j with the fix for java.lang.ClassCastException:
org.dom4j.DocumentFactory cannot be cast to org.dom4j.DocumentFactory

See: https://github.com/stapler/stapler/pull/36