message: Log command and args for the external PDF viewer.
diff: @@ -358,6 +358,7 @@ export class Viewer {
  if (args) {
  args = args.map(arg => arg.replace('%PDF%', pdfFile))
  }
  + this.extension.logger.addLogMessage(`Execute the external PDF viewer: command ${command}, args ${args}`)
  this.extension.manager.setEnvVar()
  cs.spawn(command, args, {cwd: path.dirname(sourceFile), detached: true})
  this.extension.logger.addLogMessage(`Open external viewer for ${pdfFile}`)
  