man-pages-3.11 is released

I've uploaded man-pages-3.11 into the release directory (or view the online pages). Notable changes in man-pages-3.11 are:

• A new umount(2) page has been created by splitting the umount() and umount2() material out of the old mount(2) page.
• The mount(2) page adds a description of per-process namespaces.
• Various fixes and improvements in getdents(2), including the addition of an example program.
• Many improvements and additions in signal(7), the page that provides an overview of signals on Linux.
• Numerous fixes to many other pages.