Updated documentation Specifying types for GradingPrimary attributes #1640 (#1989)

* Update documentation: Specify types for GradingPrimary attributes

Signed-off-by: sumana sree <sumanasree2705@gmail.com>

* added pivotWhite and pivotBlack types to documentation

Signed-off-by: sumana sree <sumanasree2705@gmail.com>

---------

Signed-off-by: sumana sree <sumanasree2705@gmail.com>
Co-authored-by: Doug Walker <doug.walker@autodesk.com>

Author: sumana-2705

docs/api/python/src/pyopencolorio_gradingprimary.rst

@@ -6,3 +6,42 @@
    :members:
    :undoc-members:
    :special-members: __init__, __str__
+
+   .. attribute:: brightness
+      :type: GradingRGBM
+
+   .. attribute:: clampBlack
+      :type: float
+
+   .. attribute:: clampWhite
+      :type: float
+
+   .. attribute:: contrast
+      :type: GradingRGBM
+
+   .. attribute:: exposure
+      :type: GradingRGBM
+
+   .. attribute:: gain
+      :type: GradingRGBM
+
+   .. attribute:: gamma
+      :type: GradingRGBM
+
+   .. attribute:: lift
+      :type: GradingRGBM
+
+   .. attribute:: offset
+      :type: GradingRGBM
+
+   .. attribute:: pivot
+      :type: float
+
+   .. attribute:: pivotBlack
+      :type: float
+
+   .. attribute:: pivotWhite
+      :type: float
+
+   .. attribute:: saturation
+      :type: float