Changelog for 2.102

Legend:

security fix
major bug fix
bug fix
major enhancement
enhancement

Community feedback:

no major issues
notable issues
required rollback

What's new in 2.102 (2018-01-14)

JEP-200: "Switch Remoting/XStream denylist to an allowlist " has been integrated to this release. This change implies a HIGH RISK of regressions in plugins. See this blogpost for list of plugins known to be affected, with instructions how to resolve possible problems.

Switch Remoting/XStream denylist to an allowlist. (issue 47736 , upgrade guidelines for admins and plugin maintainers, list of affected plugins)
Update Jenkins Remoting from 3.15 to 3.16. (full changelog, issue 47736 , issue 48686 )
Limit which section headers are added to the breadcrumb config outline. (issue 48773)
Reduce memory consumption for concurrent jobs when retrieving cause of blockage. (pull 3227)
Introduce new hudson.lifecycle.ExitLifecycle to exit instead of restart. (issue 47043 , Jenkins features controlled by system properties)
AtomicFileWriter was not fully atomic. Now it uses a FileChannel internally and forces a disk sync when committing. (issue 34855)
Developer: Add a constructor to ToolDescriptor so that subclasses are not required to be an inner class of their Describable. (pull 3220)