fdo#84685: writerfilter: RTF import: support \xe index entry

Change-Id: Ia957541a5997961aa86b2eb8537ebd29d3092691
(related fdo#84685): writerfilter: RTF import: support \tc TOC entry

Change-Id: Icda252e1f092707728d3a24df50fba7080e759bb