linux: remove unnecessary distro specific hostname setting

Issue: #21

linux/_linuxcontext.py

@@ -105,16 +105,8 @@ class Context(BaseContext):
 
     @staticmethod
     def set_hostname(hostname):
-        if distro == 'debian':
         with open('/etc/hostname', 'w') as f:
             f.write(hostname)
-        elif distro == 'rhel':
-            for line in fileinput.input('/etc/sysconfig/network',
-                                        inplace=1):
-                if line.startswith('HOSTNAME='):
-                    print 'HOSTNAME=%s' % hostname
-                else:
-                    print line.rstrip()
 
         with open('/etc/hosts', 'w') as f:
             f.write("127.0.0.1 localhost\n"