Fixed SETPROP() macro behaviour in config.def.h to handle escapes correctly.
xprop prints information in format PROPERTY(STRING) = "escaped string",
which causes problem with repeated Ctrl-F: any non-ascii turns into
\ooo\ooo, this later turns into \\ooo\\ooo, and so on. To de-escape
string, printf(1) is used, getting information from xargs -0; without -0
xargs will try to handle escapes by itself and also do shenanigans
with quotes, which is totally undesired.
Signed-off-by: Christoph Lohmann <20h@r-36.net>
