"new" borderlines (from 2012, 2014) defined in
offapi/com/sun/star/table/BorderLineStyle.idl
were not supported in export yet!!! Sad.
    const short FINE_DASHED = 14; (rtf)
    const short DOUBLE_THIN = 15; (rtf/doc/docx)
    const short DASH_DOT = 16; (rtf/docx)
    const short DASH_DOT_DOT = 17; (rtf/docx)

Change-Id: I085bb4c70e53241fb59a4a3c97d7741cef841412
Reviewed-on: https://gerrit.libreoffice.org/60991Reviewed-by: Justin Luth <justin_luth@sil.org>
Tested-by: Justin Luth <justin_luth@sil.org>