Fixed dimension of CylinderStructured (pyvista#577)

* CylinderStructured length fix

The structured grid generated was shorter than the length argument.

* Removed a layer of repeating points at the end of the circumference.
The dimension now provides the right number of points specified.

pyvista/utilities/geometric_objects.py

@@ -146,10 +146,6 @@ def CylinderStructured(radius=0.5, height=1.0,
     X = radius_matrix * np.cos(theta_matrix)
     Y = radius_matrix * np.sin(theta_matrix)
 
-    # Duplicate the first point to close loop
-    X = np.append(X, X[0])
-    Y = np.append(Y, Y[0])
-
     # Make all the nodes in the grid
     xx = np.array([X] * z_resolution).ravel()
     yy = np.array([Y] * z_resolution).ravel()
@@ -162,7 +158,7 @@ def CylinderStructured(radius=0.5, height=1.0,
     # Create the grid
     grid = pyvista.StructuredGrid()
     grid.points = np.c_[xx, yy, zz]
-    grid.dimensions = [nr, theta_resolution+1, z_resolution]
+    grid.dimensions = [nr, theta_resolution, z_resolution]
 
     # Orient properly in user direction
     vx = np.array([0., 0., 1.])