feat(colorcolchar): make the colorcolumn more flexible

This PR creates the ability to optionally decorate the colorcolumn(s) in
other ways.

Specifically it adds the ability to set:

  * The highlight group to highlight a colorcolumn with
  * A character to draw in a colorcolumn
  * whether the colorcolumn should mix its highlighting with the
    character in the column.

The new syntax for colorcolumn is:

set colorcolumn=[+|-]<num>[/<char>[/<hl_group>[/<flags>]]]

By default the char is ' ', and the hl_group is 'ColorColumn'

This PR does not change the existing semantics, just adds to them.

0 files changed, 0 insertions, 0 deletions