[Fusioninventory-commit] [fusinv/fusioninventory-agent] ff4df4: add _getInstallDate() to reduce complexity

[Gonéri Le Bouder]

  Branch: refs/heads/2.2.x
  Home:   https://github.com/fusinv/fusioninventory-agent
  Commit: ff4df42418c720c7b0f7da1336700de87bff191d
      https://github.com/fusinv/fusioninventory-agent/commit/ff4df42418c720c7b0f7da1336700de87bff191d
  Author: Gonéri Le Bouder <goneri at rulezlan.org>
  Date:   2013-01-19 (Sat, 19 Jan 2013)

  Changed paths:
    M lib/FusionInventory/Agent/Task/Inventory/Input/Win32/OS.pm

  Log Message:
  -----------
  add _getInstallDate() to reduce complexity

This patch add _getInstallDate() to avoid the line used before to collect $installDate.

the encodeFromRegistry was not required since installDate
is a numerical value.

I also added two tests to be sure value are define, hopefuly, this
will fix #1813.

see: #1813