Build Electron app for a specific platform
Build Electron app for a specific platform

Allow building an Electron app for a specific platform by providing an
argument. Example of building an app for Linux:

1. gulp build
2. gulp electron --platform linux-x64

xeddmc/laverna,xeddmc/laverna,brunosxs/laverna,Laverna/laverna,JerJohn15/laverna,varod/laverna,Laverna/laverna,JerJohn15/laverna,varod/laverna,brunosxs/laverna