HPCC-11157 Allow install-cluster run concurrently

1. Original install-cluster.sh is divided to two files:
  1.1.  install-cluster.sh:
       1.1.1.  top level script.
       1.1.2.  get admin user passwords.
       1.1.3.   create package for remote install
       1.1.4 .  excute install-hpcc.exp through cluster_script.py if python 2.6+ detected.
                  It allows mulitple instances run simultanously. If no suitable python
                  installed install-hpcc.exp will execute sequentially for each ip.

  1.2.  install-hpcc.exp
       1.2.1. run on each host to install and configure HPCC.
       1.2.2.  check connection logic is added. If it fails no furhter action will be
                 applied on the host.
       1.2.3. Add handling ssh/scp connection without password which is normal in cloud
                environment.
2. The original script only install if hpcc user doesn't exists on the host. The fix
    lefts the restriction to allow installation always go through. If HPCC exists and the
    image version is newer it will update it.

3. Log file is at /var/log/HPCCSystesm/cluster/XX_install-hpcc_yyyymmdd_HHMMSS.log
    For concurrent exection XX is "cc". If run sequentially it is "se".