Added correct executables for ftp and sftp mounting for ssh workspaces. Display useful error if user doesn't have these executables installed

configs/client-default.js

@@ -474,12 +474,14 @@ module.exports = function(options) {
         {
             packagePath: "plugins/c9.ide.mount/ftp",
             curlftpfsBin: options.mount.curlftpfsBin,
-            fusermountBin: options.mount.fusermountBin
+            fusermountBin: options.mount.fusermountBin,
+            ssh: options.ssh
         },
         {
             packagePath: "plugins/c9.ide.mount/sftp",
             sshfsBin: options.mount.sshfsBin,
-            fusermountBin: options.mount.fusermountBin
+            fusermountBin: options.mount.fusermountBin,
+            ssh: options.ssh
         },
         {
             packagePath: "plugins/c9.ide.upload/dragdrop",

package.json

@@ -91,7 +91,7 @@
         "c9.ide.imgeditor": "#ed89162aa7",
         "c9.ide.immediate": "#6845a93705",
         "c9.ide.installer": "#3e6f7a72c9",
-        "c9.ide.mount": "#f4e95044e6",
+        "c9.ide.mount": "#250f8d91a2",
         "c9.ide.navigate": "#f358997d93",
         "c9.ide.newresource": "#f1f0624768",
         "c9.ide.openfiles": "#28a4f5af16",