update jupyterlab deps, remove ipyvolume

binder/environment.yml

-name: improc_beginner
+name: improc_beginner_corr
 channels:
   - conda-forge
 dependencies:
@@ -11,7 +11,8 @@ dependencies:
   - ipywidgets
   - pandas
   - jupyter_contrib_nbextensions
-  - ipyvolume
   - ipympl
+  - nbgrader
   - pip:
-    - requests
\ No newline at end of file
+    - requests
+    - lckr-jupyterlab-variableinspector
\ No newline at end of file

binder/postBuild

 python installation/download_data.py
 
 mkdir PyImageCourse_beginner
-mv *.ipynb PyImageCourse_beginner/
-
-jupyter labextension install @jupyter-widgets/jupyterlab-manager --no-build
-jupyter labextension install ipyvolume --no-build
-jupyter labextension install jupyter-threejs --no-build
-jupyter labextension install itk-jupyter-widgets --no-build
-jupyter labextension install @lckr/jupyterlab_variableinspector --no-build
-jupyter labextension install jupyter-matplotlib --no-build
-
-jupyter lab build
\ No newline at end of file
+mv *.ipynb PyImageCourse_beginner/
\ No newline at end of file