Merge branch '10-kursivierung-fett-hochgestellt' into 'master'

Resolve "Kursivierung/Fett/Hochgestellt"

Closes #10

See merge request !16

schema/edxml.rng

@@ -360,7 +360,22 @@
     <define name="elem.hi">
         <element name="hi">
             <optional>
-                <attribute name="rend"/>
+                <attribute name="rend">
+                    <list>
+                        <choice>
+                            <value>bold</value>
+                            <a:documentation>Fett</a:documentation>
+                            <value>italics</value>
+                            <a:documentation>Kursiv</a:documentation>
+                            <value>sub</value>
+                            <a:documentation>Tiefgestellt</a:documentation>
+                            <value>super</value>
+                            <a:documentation>Hochgestellt</a:documentation>
+                            <value>under</value>
+                            <a:documentation>Unterstrichen</a:documentation>
+                        </choice>
+                    </list>
+                </attribute>
             </optional>
             <text/>
         </element>
@@ -829,6 +844,7 @@
             <interleave>
                 <!--<ref name="group.inline.elements"/>-->
                 <ref name="model.philological.translit"/>
+                <ref name="elem.hi"/>
                 <text/>
             </interleave>
         </element>