Update pageSizeW and pageSizeH docs

docs/containers.rst

@@ -34,6 +34,8 @@ Section settings
 
 Below are the available settings for section:
 
+-  ``pageSizeW`` Page width in twips (the default is 11906/A4 size)
+-  ``pageSizeH`` Page height in twips (the default is 16838/A4 size)
 -  ``orientation`` Page orientation, i.e. 'portrait' (default) or
    'landscape'
 -  ``marginTop`` Page margin top in twips
@@ -56,12 +58,6 @@ Below are the available settings for section:
 -  ``breakType`` Section break type (nextPage, nextColumn, continuous,
    evenPage, oddPage)
 
-The following two settings are automatically set by the use of the
-``orientation`` setting. You can alter them but that's not recommended.
-
--  ``pageSizeW`` Page width in twips
--  ``pageSizeH`` Page height in twips
-
 Page number
 ~~~~~~~~~~~