[message filter]

- take filter string and substite string
- can now replace key by another key

git-svn-id: http://moon:8086/svn/software/trunk/projects/GnuRadio@529 b431acfa-c32f-4a4a-93f1-934dc6c82436

gr-jay/grc/jay_message_filter.xml

@@ -4,13 +4,24 @@
   <key>jay_message_filter</key>
   <category>[jay]</category>
   <import>import jay</import>
-  <make>jay.message_filter()</make>
+  <make>jay.message_filter($filterString, $substString)</make>
+  <param>
+    <name>Filter String</name>
+    <key>filterString</key>
+    <value>freq_rel_Hz</value>
+    <type>string</type>
+  </param>
+  <param>
+    <name>Substitute String</name>
+    <key>substString</key>
+    <value>freq</value>
+    <type>string</type>
+  </param>
    <sink>
     <name>in</name>
     <type>message</type>
     <optional>1</optional>
   </sink>
-
   <source>
     <name>out</name>
     <type>message</type>