Animate SVG number and length properties

We add support for animation of the following SVG properties:
  azimuth
  elevation
  k1
  k2
  k3
  k4
  limitingConeAngle
  pointsAtX
  pointsAtY
  pointsAtZ
  refX
  refY
  pointsAtX
  pointsAtY
  pointsAtZ
  refX
  refY
  rx
  ry
  scale
  startOffset
  x1
  x2
  y1
  y2
  z