WIN32 startup bugfix

[David Goodenough]

At the top of zookeeper_init, a call in made to log_env(); immediately
prior to the WIN32 guarded block that calls WSAStartup().  The call to
log_env() calls gethostname(), which fails under WIN32 because WSAStartup()
hasn't been called yet.

Proposed fix, move the call to log_env() immediately below the WIN32
guarded block.  I have tried this locally working with the current 3.4.5
source, it does solve the problem.

     David Goodenough