[EDIT 2016_07_21] : when the support to ODT documents will be improved (especially the ability to open ODT documents), this commit c0fc6b1 will be no longer preferable, and we should set 'SaveAsOdt' instead of 'SaveAsHtml' as fallback in the fileSave section, this because the ODT format should have an higher priority over the html format: Little Writer aims to become a word processor, not an HTML editor (although can be also used as HTML editor).
Currently, Little Writer, is not able to open *.odt files; however the ODT documents generated by Little Writer are almost properly displayed by other word processors (like, eg. Libre Office).
Would be nice/important to implement the ability to properly display these files and also the ability to properly write/generate these files.