Update readme

README.md

@@ -36,6 +36,9 @@ can be generated:
 ```shell
 # Adds COLR to a font with SVG and vice versa
 maxmium_color my_colr_font.ttf
+
+# Adds COLR to a font with SVG and vice versa, and generates a CBDT table
+maxmium_color --bitmaps my_colr_font.ttf
 ```
 
 The intended result is a font that will Just Work in any modern browser:
@@ -44,7 +47,7 @@ The intended result is a font that will Just Work in any modern browser:
 | --- | --- | --- |
 | COLR | Chrome 98+ | https://developer.chrome.com/blog/colrv1-fonts/ |
 | SVG | Firefox, Safari | |
-| CBDT | Chrome <98 | |
+| CBDT | Chrome <98 | Only generated if you pass `--bitmaps` to `maximum_color`|
 
 Note that at time of writing Chrome 98+ prefers CBDT to COLR. Also CBDT is
 huge. So ... maybe take the resulting font and subset it per-browser if at