doc: --disableexcludepkgs=all doesn't affect just file configuration

The option `--disableexcludepkgs=all` disables all configuration
includes and excludes including packages specified on the commandline
via `--exclude=`, `-x=`, the deprecated `--excludepkgs=` and file
configuration via `--excludepkgs=`, `--includepkgs=`.

doc/command_ref.rst

@@ -168,7 +168,7 @@ Options
 
     Disable the configuration file excludes. Takes one of the following three options:
 
-    * ``all``, disables all configuration file excludes
+    * ``all``, disables all configuration excludes and includes
     * ``main``, disables excludes defined in the ``[main]`` section
     * ``repoid``, disables excludes defined for the given repository