chore(join) rm unused JOIN_PATH

Author: coderaiser

lib/join.js

@@ -9,7 +9,6 @@
         Minify      = require('minify'),
         exec        = require('execon'),
 
-        JOIN_PATH   = '/../www/join.js',
         FILE        = __dirname + '/../www/join.js',
         PREFIX      = '/join';