Allow easy adding configuration pages from modules to custom sub-tabs

Actually you can already add configuration pages to tabs setting it this way in AdminTabs to do the trick:
Class:AdminModules&configure=yourmoduleclass
Module:yourmoduleclass
but the token generated is wrong since the string "classname" contains extra parameters breaking the token.

With this simple fix the parameter "&configure" is excluded when calculting the token giving the correct token and appending it again at the end of the url.