Base knife-edge scan analysis implementation

Hi @lleguy @mercadil,

This is an example of a base implementation, specifically the knife edge scan analysis from Laurent's tb.knife_edge. This is agnostic from xarray data format, thus this can be easily used on other means, such as on a Karabo device.

I also have found out that there could be problems with using bisect especially with repetitive elements. I use slicing instead to find the valid range.

src/toolbox_scs/base/tests/test_knife_edge.py

@@ -103,7 +103,8 @@ def test_knife_edge_base():
     np.testing.assert_allclose(p0, popt, atol=1e-1)
 
     # Test flipped data
-    popt, _ = knife_edge_base(x, eff_y[::-1])
+    popt, _ = knife_edge_base(x, eff_y[:, ::-1])
+    p0[1] = abs(p0[1])  # Absolute value when flipped
     np.testing.assert_allclose(p0, popt, atol=1e-1)