Update utils for CRF install and artifacts removal

Author: C-Achard

docs/source/guides/utils_module_guide.rst

@@ -51,7 +51,7 @@ Break down large images into smaller cubes, optimal for training.
 
 .. note::
     This utility is only available if you have installed the `pydensecrf` package.
-    You may install it by using the command ``pip install cellseg3d[crf]``.
+    You may install it by using the command ``pip install pydensecrf@git+https://github.com/lucasb-eyer/pydensecrf.git#egg=master``.
 
 | Refines semantic predictions by pairing them with the original image.
 | For a list of parameters, see the :doc:`CRF API page<../code/_autosummary/napari_cellseg3d.code_models.crf>`.
@@ -83,6 +83,11 @@ Global metrics :
 .. hint::
     Check the ``notebooks`` folder for examples of plots using the statistics CSV file.
 
+10. Clear large labels
+----------------------
+| Clears labels that are larger than a given threshold.
+| This is useful for removing artifacts that are larger than the objects of interest.
+
 Source code
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