update URLs to 1.5.2, tried to fix make_image...

Accumulo 1.5.1 no longer exists, so I changed it to 1.5.2.  Unfortunately, I encountered a host of HADOOP configuration problems.  I solved some of them but got stuck on 

```
mkdir: Call From MYHOSTNAME/172.17.0.32 to MYHOSTNAME:8020 failed on connection exception: java.net.ConnectException: Connection refused; For more details see:  http://wiki.apache.org/hadoop/ConnectionRefused
```

from `init_accumulo.sh` within `make_image.sh`