now: require a path (eg: `now .`)

bin/now

@@ -12,6 +12,7 @@ import ms from 'ms';
 import os from 'os';
 
 program
+.usage('[options] <path>')
 .option('-d, --debug', 'Debug mode [off]', false)
 .option('-f, --force', 'Force a new deployment even if nothing has changed', false)
 .option('-L, --login', 'Configure login')
@@ -25,7 +26,9 @@ if (path) {
     path = resolve(process.cwd(), path);
   }
 } else {
-  path = process.cwd();
+  error('Missing path. To deploy this directory, run `now .`');
+  program.outputHelp();
+  process.exit(1);
 }
 
 let config;