Added simple python usage example using scikit-image

src/Python/test_cells3d.py

+"""
+This small example loads the cells3d dataset from scikit-image into LEVERSC for visualization
+"""
+import numpy as np
+from skimage.data import cells3d
+
+import leversc
+
+# Load the cells3d dataset
+cells = cells3d()
+# Rearrange the dimensions to be in expected order (c,z,y,x) for row-major numpy array
+cellsC = np.copy(np.transpose(cells,[1,0,2,3]), order='C')
+
+# Set up the image metadata: such as physical voxel size, and channel names
+# See: https://scikit-image.org/docs/0.18.x/api/skimage.data.html?highlight=cells3d#skimage.data.cells3d
+imD = {"PixelPhysicalSize": [0.29,0.26,0.26],
+    "ChannelNames": ["Membrane","Nuclei"]}
+# Send data to the LEVERSC viewer
+lsc = leversc.leversc(im=cellsC, imD=imD)