errors: Added custom 'linux_mount_failed' message
actions: Added 'post-comm' customization step
Reboot the VM right after Parallels Tools installation/upgrade [GH-133]
Added wrapper for action 'handle_forwarded port_collisions'.

It allows to skip calling the builtin action if port forwarding is not supported (PD < 10)
Release v1.2.1

* master:
  Added wrapper for action 'handle_forwarded port_collisions'.
  Reboot the VM right after Parallels Tools installation/upgrade [GH-133]
  actions: Added 'post-comm' customization step
  errors: Added custom 'linux_mount_failed' message