Miscutils: fix for send_email error on DEV site

* For the DEV site send_email function was failing while trying to
  concatenate list and string (because the CFG_SITE_ADMIN_EMAIL
  was not a list).
The problem is in the line 255:
server.sendmail(fromaddr, toaddr + bccaddr, body)
if the toaddr is a string, then it gives this error:
TypeError: cannot concatenate 'str' and 'list' objects (mailutils.py:255:send_email)