Firefox: implement toolbar button and popup

platform/firefox/install.rdf

@@ -17,7 +17,7 @@
         <targetApplication>
             <r:Description>
                 <id>{ec8030f7-c20a-464f-9b0e-13a3a9e97384}</id>
-                <minVersion>24.0</minVersion>
+                <minVersion>29.0</minVersion>
                 <maxVersion>37.0</maxVersion>
             </r:Description>
         </targetApplication>
@@ -26,7 +26,7 @@
         <targetApplication>
             <r:Description>
                 <id>{92650c4d-4b8e-4d2a-b7eb-24ecf4f6b63a}</id>
-                <minVersion>2.21</minVersion>
+                <minVersion>2.26</minVersion>
                 <maxVersion>2.34</maxVersion>
             </r:Description>
         </targetApplication>