Merge branch '170622' of github.com:jwpi/util-linux

* '170622' of github.com:jwpi/util-linux:
  Docs: move option naming to howto-contribute.txt
  Docs: update howto-usage-function.txt
  Docs: add a comment for constants to boilerplate.c
  include/c.h: add USAGE_COMMANDS and USAGE_COLUMNS

diff --cc include/c.h
Simple merge

diff --cc login-utils/lslogins.c
Simple merge