Fix file list enabled/disabled logic

* Files that are either 100% downloaded OR streamble should be enabled
* Disabled files should not be clickable

This fixes both bugs.

renderer/lib/dispatcher.js

@@ -24,7 +24,7 @@ function dispatcher (...args) {
       // Don't click on whatever is below the button
       e.stopPropagation()
       // Don't regisiter clicks on disabled buttons
-      if (e.target.classList.contains('disabled')) return
+      if (e.currentTarget.classList.contains('disabled')) return
       _dispatch.apply(null, args)
     }
   }

renderer/views/torrent-list.js

@@ -207,10 +207,11 @@ function TorrentList (state) {
   // Show a single torrentSummary file in the details view for a single torrent
   function renderFileRow (torrentSummary, file, index) {
     // First, find out how much of the file we've downloaded
-    var isDone = file.numPiecesPresent === file.numPieces
+    var isDone = false
     var progress = ''
     if (torrentSummary.progress && torrentSummary.progress.files) {
       var fileProg = torrentSummary.progress.files[index]
+      isDone = fileProg.numPiecesPresent === fileProg.numPieces
       progress = Math.round(100 * fileProg.numPiecesPresent / fileProg.numPieces) + '%'
     }