doc: desc +/- value prefix for opts/configs in NEWS/CHANGES

Author: xdelaruelle

NEWS.rst

@@ -136,6 +136,18 @@ Modules 5.3.0 (not yet released)
   When set and if a variant is specified in search query, variants and their
   possible values are reported along the module they are associated to on
   :subcmd:`avail` command output.
+* Accept value starting with ``+`` or ``-`` characters on
+  :option:`--output`/:option:`-o` command-line switches to indicate value
+  should respectively be appended to or subtracted from current configuration
+  option value.
+* Accept value starting with ``+`` or ``-`` characters on
+  :mconfig:`avail_output`, :mconfig:`avail_terse_output`,
+  :mconfig:`list_output`, :mconfig:`list_terse_output`, :mconfig:`colors`,
+  :mconfig:`protected_envvars`, :mconfig:`shells_with_ksh_fpath`,
+  :mconfig:`tag_abbrev`, :mconfig:`tag_color_name`,
+  :mconfig:`variant_shortcut` configuration options to indicate value
+  should respectively be appended to or subtracted from current configuration
+  option value.
 
 
 .. _5.2 release notes:

doc/source/changes.rst

@@ -822,6 +822,12 @@ The following command line switches appeared on Modules 5.
 | 5.3        | :option:`--ignore-cache`, :option:`--ignore-user-rc`            |
 +------------+-----------------------------------------------------------------+
 
+:option:`--output`
+
+ Starting Modules 5.3, this command line switch accepts value prefixed by
+ ``+`` or ``-`` which means value should respectively be appended to or
+ subtracted from current configuration option value.
+
 Module Sub-Commands
 """""""""""""""""""
 
@@ -1063,3 +1069,15 @@ The following Modules configuration option has been introduced on Modules 5.
  Starting version 5.3, element ``variantifspec`` is added to the list of
  accepted values. It is added to the default value list of both configuration
  options.
+
+ Starting Modules 5.3, these configuration options accept value prefixed by
+ ``+`` or ``-`` which means value should respectively be appended to or
+ subtracted from current configuration option value.
+
+:mconfig:`list_output`, :mconfig:`list_terse_output`, :mconfig:`colors`,
+:mconfig:`protected_envvars`, :mconfig:`shells_with_ksh_fpath`,
+:mconfig:`tag_abbrev`, :mconfig:`tag_color_name`, :mconfig:`variant_shortcut`
+
+ Starting Modules 5.3, these configuration options accept value prefixed by
+ ``+`` or ``-`` which means value should respectively be appended to or
+ subtracted from current configuration option value.