Adjust PyramidROIAlign layer shape comment

For PyramidROIAlign's output shape, use pool_height and pool_width instead of height and width to avoid confusion with those of feature_maps.

mrcnn/model.py

@@ -345,18 +345,18 @@ class PyramidROIAlign(KE.Layer):
     """Implements ROI Pooling on multiple levels of the feature pyramid.
 
     Params:
-    - pool_shape: [height, width] of the output pooled regions. Usually [7, 7]
+    - pool_shape: [pool_height, pool_width] of the output pooled regions. Usually [7, 7]
 
     Inputs:
     - boxes: [batch, num_boxes, (y1, x1, y2, x2)] in normalized
              coordinates. Possibly padded with zeros if not enough
              boxes to fill the array.
     - image_meta: [batch, (meta data)] Image details. See compose_image_meta()
-    - Feature maps: List of feature maps from different levels of the pyramid.
+    - feature_maps: List of feature maps from different levels of the pyramid.
                     Each is [batch, height, width, channels]
 
     Output:
-    Pooled regions in the shape: [batch, num_boxes, height, width, channels].
+    Pooled regions in the shape: [batch, num_boxes, pool_height, pool_width, channels].
     The width and height are those specific in the pool_shape in the layer
     constructor.
     """