SwTableBox::IsValidNumTxtNd: Allow trivial formatting
SwTableBox::IsValidNumTxtNd: Allow trivial formatting

Not allowing flys or footnotes during string -> number conversion is
fine, but I don't see what's the reason for rejecting simple formatting
(like bold) completely.

Change-Id: I8f54aebeb6ea35d099a88570d3f7d365c7325dc0

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core