Merge pull request #782 from parente/daozzg-master

Update all R libs in all-spark-notebook for Spark 2.4 

all-spark-notebook/Dockerfile

@@ -24,10 +24,10 @@ USER $NB_UID
 
 # R packages
 RUN conda install --quiet --yes \
-    'r-base=3.4.1' \
+    'r-base=3.5.1' \
     'r-irkernel=0.8*' \
-    'r-ggplot2=2.2*' \
-    'r-sparklyr=0.7*' \
+    'r-ggplot2=3.1*' \
+    'r-sparklyr=0.9*' \
     'r-rcurl=1.95*' && \
     conda clean -tipsy && \
     fix-permissions $CONDA_DIR && \