... before adding any attributes, so that the attributes don't
erroneously get added to the paragraph element.

Also fix the problem that if you set "ODF format version" to 1.1 or 1.2,
export asserts in SvXMLNamespaceMap::GetQNameByKey() because the "loext"
namespace isn't registered, and creates an invalid <p> element.

Change-Id: I637f9d3ff746d877ced480e35ef53f4545a06a4b