read m:oMathPara

I'm unsure on what the difference to o:Math actually is, so just make
sure the element and its contents are not ignored and each contained
m:oMath will be read in separately.

writerfilter/source/ooxml/model.xml

@@ -23624,5 +23624,6 @@
     <resource name="glossaryDocument" resource="Stream" tag="content"/>
     <resource name="CT_TxbxContent" resource="Stream" tag="shape"/>
     <resource name="CT_OMath" resource="Math" tag="math"/>
+    <resource name="CT_OMathPara" resource="Stream" tag="math"/>
   </namespace>
 </model>