Update catalogs config after discussion

Legacy catalog keeps the existing ID and URL, to avoid any problems
with older client versions

catalog/stable-2018-catalog/template.xml

@@ -1,10 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<!--Template catalog - copy and modify for your site as required-->
 <PropertyList>
   <template>
-	  <version n="0">2018.1.*</version>
-	  <version n="1">2018.2.*</version>
-	  <version n="2">2018.3.*</version>
+	  <version n="0">2018.3.*</version>
     <id>org.flightgear.fgaddon.stable_2018</id>
     <license>GPL</license>
     <url>http://mirrors.ibiblio.org/flightgear/ftp/Aircraft-2018/catalog.xml</url>
@@ -16,22 +13,35 @@
     <alternate-version>
 	    <version>2019.*</version>
 	    <version>2018.4.*</version>
+      <url>http://mirrors.ibiblio.org/flightgear/ftp/Aircraft-trunk/catalog.xml</url>
+      <id>org.flightgear.fgaddon.trunk</id>
+    </alternate-version>
+
+
+    <!-- alternate version previously did not allow multiple version entries, so we
+    duplicate the alternate version here -->
+    <alternate-version>
+      <version>2018.2.*</version>
+      <url>http://mirrors.ibiblio.org/flightgear/ftp/Aircraft/catalog.xml</url>
+      <id>org.flightgear.fgaddon</id>
+    </alternate-version>
+
+	 <alternate-version>
+      <version>2018.1.*</version>
       <url>http://mirrors.ibiblio.org/flightgear/ftp/Aircraft/catalog.xml</url>
       <id>org.flightgear.fgaddon</id>
     </alternate-version>
 
     <alternate-version>
       <version>2017.*</version>
-      <url>http://mirrors.ibiblio.org/flightgear/ftp/Aircraft-legacy/catalog.xml</url>
-      <id>org.flightgear.fgaddon.legacy</id>
+      <url>http://mirrors.ibiblio.org/flightgear/ftp/Aircraft/catalog.xml</url>
+      <id>org.flightgear.fgaddon</id>
     </alternate-version>
 
-    <!-- alternate version previously did not allow multiple version entries, so we
-    duplicate the alternate version here -->
     <alternate-version>
       <version>2016.*</version>
-      <url>http://mirrors.ibiblio.org/flightgear/ftp/Aircraft-legacy/catalog.xml</url>
-      <id>org.flightgear.fgaddon.legacy</id>
+      <url>http://mirrors.ibiblio.org/flightgear/ftp/Aircraft/catalog.xml</url>
+      <id>org.flightgear.fgaddon</id>
     </alternate-version>
     </template>
 </PropertyList>