Better checks for compose version in template for swarm

Cherry pick from: #16

Author: yamalight

src/docker/templates/compose.js

@@ -23,7 +23,7 @@ const updateCompose = ({username, baseName, serverConfig, composePath, util, res
   // read compose file
   const compose = yaml.safeLoad(fs.readFileSync(composePath, 'utf8'));
 
-  if (serverConfig.swarm && compose.version !== '3') {
+  if (serverConfig.swarm && typeof compose.version === 'string' && !compose.version.startsWith('3')) {
     util.logger.debug('Compose file should be of version 3!');
     util.writeStatus(resultStream, {
       message: 'Running in swarm mode, can only deploy docker-compose file of version 3!',