Added Republic Wireless gateway to providers.js

Email to SMS is only available if the user allows it in the settings of the Republic Wireless app, but it makes sense to go ahead and add support for the users that do use it.

lib/providers.js

@@ -14,6 +14,7 @@ module.exports = {
     '%s@txt.att.net',
     '%s@txt.windmobile.ca',
     '%s@vtext.com',
+    '%s@text.republicwireless.com'
 
     //'%s@sms.edgewireless.com',  // slow
   ],