Added features and new programs
  - IsMember will now remove spaces from strings
  - MrPSD does not pass "dt" to MrFFT, so frequencies need to be un/normalized.
  - MrLayout has a numerical tolerance for column and row sizes.
  - ssm_to_hms can return a numeric time or a time vector
  - improved documentation
New programs:
  - MrPlane3D will create a plane in three dimensions, when given three points to define the plane.
  - MrDefaultColor is a wrapper for cgDefaultColor and will work for up to 256 colors.
  - MrIndexRange replaces GetIndexRange and accepts a single data range