Dev/rosenblatttransform (#241)

- added rosenblatttransform 
- added 3x3 eta methods 
- interpolation can be used with various eta functions
- added documentation for interpolation, eta calculation 
- exposed full eta struct in python 
- disable ClusterFinder for 2x2 clusters 
- factory function for ClusterVector

---------

Co-authored-by: Dhanya Thattil <dhanya.thattil@psi.ch>
Co-authored-by: Erik Fröjdh <erik.frojdh@psi.ch>

docs/src/index.rst

@@ -29,6 +29,8 @@ AARE
     pyCtbRawFile
     pyClusterFile
     pyClusterVector
+    pyCluster
+    pyInterpolation
     pyJungfrauDataFile
     pyRawFile
     pyRawMasterFile
@@ -47,10 +49,12 @@ AARE
     Frame
     File
     Dtype
+    Cluster
     ClusterFinder
     ClusterFinderMT
     ClusterFile
     ClusterVector
+    Interpolation
     JungfrauDataFile
     Pedestal
     RawFile