Fix rich text roundtrip through ODF. [#737039]

	* openoffice-read.c (odf_push_text_p): initialize new field
	span_style_list
	(odf_pop_text_p): free span_style_list
	(odf_text_content_end): apply text styles here
	(odf_text_span_end): rather than here
	(odf_text_span_start): save the ssi also in span_style_list
	(openoffice_file_open): handle span_style_list