Merge branch 'more' of https://github.com/kerolasa/util-linux

Merge branch 'more' of https://github.com/kerolasa/util-linux

* 'more' of https://github.com/kerolasa/util-linux:
  more: refactor and clarify code
  more: add display_file() to show files and stdin
  more: simplify initterm()
  more: move currently open file to control structure
  more: move code blocks from more_key_command() to functions
  more: move runtime usage output to a function
  more: restructure print_buf() if-else with continue
  more: tell in run time help what the 'v' will execute as editor
  more: drop setuid permissions before executing anything
  more: do not allocate shell command buffer from stack
  more: replace siglongjmp() and signal() calls with signalfd()