c-ares version 1.7.2

Changed:

 o Added ares_parse_mx_reply()

Fixed:

 o ares_init: Last, not first instance of domain or search should win
 o improve alternative definition of bool
 o fix VS2010 compiler warnings

Thanks go to these friendly people for their efforts and contributions:

 Yang Tse, Tor Arntsen, Peter Pentchev, Jeremy Lal, Jakub Hrozek

Have fun!