Don't use editor.{begin|commit}Transaction

Don't use editor.{begin|commit}Transaction

This solves the following error (but I'm not sure if not using transactions
at all is the "real" solution ...):

Uncaught TypeError: undefined is not a function

At .../Applications/Atom.app/Contents/Resources/app.asar/src/text-editor.js:1156

TypeError: undefined is not a function
  at TextEditor.module.exports.TextEditor.beginTransaction (.../Applications/Atom.app/Contents/Resources/app.asar/src/text-editor.js:1156:26)
  at .../lib/pipe.coffee:37:14
  at space-pen-div.<anonymous> (.../lib/command-view.coffee:32:7)
  at space-pen-div.jQuery.event.dispatch (.../node_modules/atom-space-pen-views/node_modules/space-pen/node_modules/jquery/dist/jquery.js:4435:9)
  at space-pen-div.elemData.handle (.../node_modules/atom-space-pen-views/node_modules/space-pen/node_modules/jquery/dist/jquery.js:4121:28)
  at KeymapManager.module.exports.KeymapManager.dispatchCommandEvent (.../Applications/Atom.app/Contents/Resources/app.asar/node_modules/atom-keymap/lib/keymap-manager.js:520:16)
  at KeymapManager.module.exports.KeymapManager.handleKeyboardEvent (.../Applications/Atom.app/Contents/Resources/app.asar/node_modules/atom-keymap/lib/keymap-manager.js:355:22)
  at HTMLDocument.module.exports.WindowEventHandler.onKeydown (.../Applications/Atom.app/Contents/Resources/app.asar/src/window-event-handler.js:180:20)