CHANGED: new non-volatile encryption key

 * Use new encryption key instead of mac address
   * Windows: use wmic to fetch bios serial
   * UNIX: use /etc/machine-id
   * OS X: Use computer's serial number
 * Automatically re-encrypts data at startup, writes new data automatically after
   successfull pack launch
Merge pull request #844 from jikuja/fixes_for_v1.4.4

CHANGED: new non-volatile encryption key