9718 update mandoc to 1.14.4

*** 982,998 ****
  
       nop body
               Execute the rest of the input line as a request or macro line.
               Currently unsupported.
  
!      nr register [+|-]expression
               Define or change a register.  A register is an arbitrary string
               value that defines some sort of state, which influences parsing
               and/or formatting.  For the syntax of expression, see Numerical
               expressions below.  If it is prefixed by a sign, the register
               will be incremented or decremented instead of assigned to.
  
               The following register is handled specially:
  
               nS      If set to a positive integer value, certain mdoc(5)
                       macros will behave in the same way as in the SYNOPSIS
                       section.  If set to 0, these macros will behave in the
--- 982,1002 ----
  
       nop body
               Execute the rest of the input line as a request or macro line.
               Currently unsupported.
  
!      nr register [+|-]expression [stepsize]
               Define or change a register.  A register is an arbitrary string
               value that defines some sort of state, which influences parsing
               and/or formatting.  For the syntax of expression, see Numerical
               expressions below.  If it is prefixed by a sign, the register
               will be incremented or decremented instead of assigned to.
  
+              The stepsize is used by the \n+ auto-increment feature.  It
+              remains unchanged when omitted while changing an existing
+              register, and it defaults to 0 when defining a new register.
+ 
               The following register is handled specially:
  
               nS      If set to a positive integer value, certain mdoc(5)
                       macros will behave in the same way as in the SYNOPSIS
                       section.  If set to 0, these macros will behave in the
*** 1086,1096 ****
               currently ignored.
  
       rchar glyph ...
               Remove glyph definitions.  Currently unsupported.
  
!      rd [prompt [agument ...]]
               Read from standard input.  Currently ignored.
  
       recursionlimit maxrec maxtail
               Set the maximum stack depth for recursive macros.  This is a
               Heirloom extension and currently ignored.
--- 1090,1100 ----
               currently ignored.
  
       rchar glyph ...
               Remove glyph definitions.  Currently unsupported.
  
!      rd [prompt [argument ...]]
               Read from standard input.  Currently ignored.
  
       recursionlimit maxrec maxtail
               Set the maximum stack depth for recursive macros.  This is a
               Heirloom extension and currently ignored.
*** 1515,1527 ****
       short names, there are variants \mc and \m(cc.
  
     \N'number'
       Character number on the current font.
  
!    \n[name]
       Interpolate the number register name.  For short names, there are
!      variants \nc and \n(cc.
  
     \o'string'
       Overstrike, writing all the characters contained in the string to the
       same output position.  In terminal and HTML output modes, only the last
       one of the characters is visible.
--- 1519,1533 ----
       short names, there are variants \mc and \m(cc.
  
     \N'number'
       Character number on the current font.
  
!    \n[+|-][name]
       Interpolate the number register name.  For short names, there are
!      variants \nc and \n(cc.  If the optional sign is specified, the register
!      is first incremented or decremented by the stepsize that was specified in
!      the relevant nr request, and the changed value is interpolated.
  
     \o'string'
       Overstrike, writing all the characters contained in the string to the
       same output position.  In terminal and HTML output modes, only the last
       one of the characters is visible.
*** 1628,1633 ****
  
  AUTHORS
       This roff reference was written by Kristaps Dzonsons <kristaps@bsd.lv>
       and Ingo Schwarze <schwarze@openbsd.org>.
  
! illumos                          July 5, 2017                          illumos
--- 1634,1639 ----
  
  AUTHORS
       This roff reference was written by Kristaps Dzonsons <kristaps@bsd.lv>
       and Ingo Schwarze <schwarze@openbsd.org>.
  
! illumos                         April 10, 2018                         illumos