Add local hostname to the 127.0.0.1 entry

The default task will replace my /etc/hosts from:

127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4 hadoop-master
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6

to

127.0.0.1 localhost

Breaking some parts of the OS because the hostname of the machine ("hadoop-master" in my case) is not bound to 127.0.0.1 anymore.