Allow pass filename cmd line

https://github.com/mifi/lossless-cut/issues/9

src/index.js

@@ -48,3 +48,10 @@ app.on('activate', () => {
     createWindow();
   }
 });
+
+electron.ipcMain.on('renderer-ready', () => {
+  if (!isDev) {
+    const fileToOpen = process.argv[1];
+    if (fileToOpen) mainWindow.webContents.send('file-opened', [fileToOpen]);
+  }
+});

src/renderer.jsx

@@ -111,6 +111,8 @@ class App extends React.Component {
     keyboardJs.bind('e', () => this.cutClick());
     keyboardJs.bind('i', () => this.setCutStart());
     keyboardJs.bind('o', () => this.setCutEnd());
+
+    electron.ipcRenderer.send('renderer-ready');
   }
 
   onPlay(playing) {