[node] added local_excecute method in nodes

            default is SOFT_VM_POWEROFF

        '''

        if vm_names is None:

            #fetch all vm names in hypervisor

            vm_names = [vm.get_name() for vm in self.hv_handle._vm_list]

        logging.debug('stop_vm: stopping vms %s' % vm_names)

        for vm in vm_names:

                logging.warning('Error while starting %s: %s' % (vm ,err))

                continue

            logging.info('start_vm: vm %s starting' % vm)

    @pure

    def execute_command(self, command):

        '''

        Excecutes the given command on the local hypervisor

        :param command: the command to excecute as it would be typed on a shell

            prompt

        :type command: :class:`str`

        '''

        result = self.hv_handle.local_excecute(command)

        return result

from libvirtwrapper import *

from exceptions import *

import subprocess

class KvmHypervisor(LibvirtHypervisor):

        raise VMError('Virtual Machine %s not found: '% name)   

    def local_excecute(self, command):

        '''

        Excecutes the command given in command on the local host

        Returns a tuple with (stdout, stderr) from the process that has

        been executed

        ..warning:: This is a dangerous function as it gives the command given

        in paramter to a shell prompt, anything can then be executed locally

        ..warning:: If the command given is a long processing one, this may be

            a deadlock to the node be carefull !

        :param command: the command to execute with it's arguments

        :type command: :class:`str`

        '''

        #FIXME: stop using shell=true and parse arguments with shlex.split()

        p = subprocess.Popen(command, shell=True,

                            bufsize = -1,

                            stdin=subprocess.PIPE,

                            stdout=subprocess.PIPE,

                            stderr=subprocess.PIPE)

        result = p.communicate()

        return result

    def get_network_conf(self):

        raise NotImplementedError