refs #404 Added human-readable plugin names

* Added new "identifier" attribute in JSON metadata files
* "identifier" is now the one that makes plugins unique
* "name" attribute is a human-readable name

src/plugins/simulator/fs9/simulator_fs9.json

@@ -1,5 +1,6 @@
 {
-    "name" : "swift_generic_fs9",
+    "identifier" : "swift_generic_fs9",
+    "name" : "Microsoft Flight Simulator 2004",
     "simulator" : "fs9",
     "description" : "Microsoft Flight Simulator 2004"
 }

src/plugins/simulator/fsx/simulator_fsx.json

@@ -1,5 +1,6 @@
 {
-    "name" : "swift_generic_fsx",
+    "identifier" : "swift_generic_fsx",
+    "name" : "Microsoft Flight Simulator X",
     "simulator" : "fsx",
     "description" : "Microsoft Flight Simulator X (2006)"
 }

src/plugins/simulator/xplane/simulator_xplane.json

@@ -1,5 +1,6 @@
 {
-    "name" : "swift_generic_xplane",
+    "identifier" : "swift_generic_xplane",
+    "name" : "X-Plane",
     "simulator" : "xplane",
     "description" : "X-Plane support via the xbus plugin"
 }