underlining white space
In BB1.6 it is not possible to underline spaces and tabs
as it is usual in text processors such as Microsoft Word or Open Office.
In order to be able to use BB based applications in an office environment
for producing professional style text documents it is required to have
underlined white spaces. The same applies to strikethrough.
A proposal by J. Templ for adding this feature exists in CPC 1.7 rc5.
Refers to CPC 1.7 rc5 change list number 33, 34, and 66.
underlining white space added. Refs: #60.
As proposed by Josef Templ and Helmut Zinn in CPC 1.7 rc5
but without a flag for switching it on and off.
The special treatment of printer frames has been commented because it was not
possible to produce a test case where it shows a difference.
Signed-off-by: Josef Templ <firstname.lastname@example.org>