Settings: SlimRecents scaling + lefty mode (3/3)

- Add scaling mode....user can scale the overall size down (especially for the
      user with stock dpi requested)

    - Add lefty mode. Recent panel shows up on the left edge instead of the right edge
      for left handed people.

Both are one time accesibility settings. So we put it there.

Change-Id: Ibd3382a94c65699cfdd00559a9045bdc91c558bb