Support "json" for config/option elements (#37)

Author: mlocati

src/main/resources/concrete-cif-1.0.xsd

@@ -343,6 +343,7 @@
                                 </xs:simpleType>
                             </xs:attribute>
                             <xs:attribute name="overwrite" type="xs:boolean" use="optional" />
+                            <xs:attribute name="json" type="xs:boolean" use="optional" />
                             <xs:attribute name="package" type="handle" use="required" />
                         </xs:extension>
                     </xs:simpleContent>

src/test/resources/cifs-bad/config-7.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0"?>
+<concrete5-cif version="1.0">
+    <config>
+        <option name="o1" json="wrong" package="">foo</option>
+    </config>
+</concrete5-cif>

src/test/resources/cifs-good/config.xml

@@ -15,5 +15,7 @@
         <option name="o12" storage="database" package="my_package">foo</option>
         <option name="o13" storage="database" overwrite="false" package="my_package">foo</option>
         <option name="o14" storage="database" overwrite="true" package="my_package">foo</option>
+        <option name="o14" storage="database" overwrite="true" json="false" package="my_package">foo</option>
+        <option name="o14" storage="database" overwrite="true" json="true" package="my_package">true</option>
     </config>
 </concrete5-cif>