Misc: Add missing entries to the deprecated-3.0 category

Fixes jquery#1116
Closes jquery#1117

Author: TiTi

entries/jQuery.parseJSON.xml

@@ -37,4 +37,5 @@ alert( obj.name === "John" );
   </example>
   <category slug="utilities"/>
   <category slug="version/1.4.1"/>
+  <category slug="deprecated/deprecated-3.0"/>
 </entry>

entries/jQuery.unique.xml

@@ -43,4 +43,5 @@ $( "div:eq(2)" ).text( "Post-unique there are " + divs.length + " elements." )
   </example>
   <category slug="utilities"/>
   <category slug="version/1.1.3"/>
+  <category slug="deprecated/deprecated-3.0"/>
 </entry>

entries/toggleClass.xml

@@ -208,5 +208,6 @@ $( "a" ).on( "click", function( event ) {
     <longdesc>
       <div class="warning"><strong>This signature (only!) is deprecated as of jQuery 3.0</strong>.</div>
     </longdesc>
+    <category slug="deprecated/deprecated-3.0"/>
   </entry>
 </entries>