Update OpenDocument-v1.4-part3-schema-tracked.odt

Various editorial corrections:

- 19.390 (Office-4140) : Updated the value of field 'Version' to "1.4" ; changed the fixed value of attribute office:version to "1.4"; corrected the spelling of "attriibute" in the Note inserted

- 19.506 : accepted deletion of a blank heading that had been inserted in a previous edit, to ensure that section numbering is correct whether or not tracked changes are showing.

- 19.597.6 (Office-3741) : Adjusted the deletion of this sub-section so that the sub-section number and reference field remain, to avoid re-numbering sub-sections 19.597.7 - 9, and to avoid breaking the cross-reference link to the deleted attribute in Appendix G.