anchor.diff:  for example, _3W_ selects 3 consecutive words and _3w_ select the third word on
   the right of selection end.
   
  -* _space_: when used with count, keep only the counth selection
  -* _alt-space_: when used with count, remove the counth selection
  + * _space_: when used with count, keep only the counth selection
  + * _alt-space_: when used with count, remove the counth selection
   
   Changes
   -------
  
positive.code: Using alt-i and alt-a, you can select some text object, the starting
  point is always the last character of the selection.
  
  * _b_, _(_ or _)_: select the enclosing parenthesis
  * _B_, _{_ or _}_: select the enclosing {} block
  * _[_ or _]_: select the enclosing [] block
  * _<_ or _>_: select the enclosing <> block
  * w: select the whole word
  * W: select the whole WORD
  
  When it makes sense, _alt-i_ selects the inner object and alt-a the whole
  object. For example _alt-i_ ( will only select the inside of the parenthesis,
  
negative.code: 
  existing highlighters are:
  
   * *highlight_selections*: used to make current selection visible
   * *expand_tabs*: expand tabs to next 8 multiple column (to make configurable)
   * *number_lines*: show line numbers
   * *group*: highlighter group, containing other highlighters. takes one
              parameter, <group_name>. useful when multiple highlighters work
              together and need to be removed as one. Adding and removing from
              a group can be done using
              :addhl -group <group> <highlighter_name> <highlighter_parameters...>
              :rmhl  -group <group> <highlighter_name>
   * *regex*: highlight a regex, takes the regex as first parameter, followed by
              any number of color spec parameters.
              color spec format is: <capture_id>:<fg_color>[,<bg_color>]
              For example:
              :addhl regex //(\h+TODO:)?[^\n]+ 0:cyan 1:yellow,red
              will highlight C++ style comments in cyan, with an eventual
              'TODO:' in yellow on red background.
  
  Filters
  -------
  