[PPP-3272] - Update all current "infocenter" references to "mind touch"

- Updated link references from infocenter.pentaho.com to help.pentaho.com.
    - Tweaked references to InfoCenter to be consistently spelled (casing)
      InfoCenter is how the Doc team wants to refer to the help documentation
      at this point. No reference to MindTouch since it is only the
      implementation vehicle.