fix etherpad_to_opale

etherpad_to_opale/etherpad_to_opale.ant

@@ -38,7 +38,9 @@
                 <include name="*.html"/>
             </fileset>
         </copy> 
-        <exec dir="../etherpad_to_hdoc" executable="run.sh"/>
+        <exec executable="/bin/bash" dir="../etherpad_to_hdoc">
+            <arg value="../etherpad_to_hdoc/run.sh"/>
+        </exec>
     </target>
     
     <target name="to_opale_init">
@@ -53,7 +55,9 @@
         <copy todir="${opa_in}">
             <fileset dir="${eth_out}"/>
         </copy>
-        <exec dir="../hdoc_to_opale" executable="run.sh"/>
+        <exec executable="/bin/bash" dir="../hdoc_to_opale">
+            <arg value="../hdoc_to_opale/run.sh"/>
+        </exec>
     </target>
     
     <target name="to_opale_windows" if="${is_windows}">