Merge branch 'add_python' into 'master'

Adding python3

See merge request centos-e3!1

Dockerfile

@@ -4,14 +4,14 @@ LABEL maintainer "benjamin.bertrand@esss.se"
 
 RUN yum update -y \
   # Use IUS repository to install recent version of git (git2u)
-  && yum -y install  https://centos7.iuscommunity.org/ius-release.rpm \
+  && yum -y install  https://repo.ius.io/ius-release-el7.rpm \
   && yum install -y \
     file \
     patch \
     tree \
     m4 \
     gcc-c++ \
-    git2u-all \
+    git224-all \
     expectk \
     tclx \
     graphviz \
@@ -27,9 +27,7 @@ RUN yum update -y \
     opencv-devel \
     wget \
     sudo \
-    GraphicsMagick-devel \
-    ImageMagick-devel \
-    ImageMagick-c++-devel \
+    python3 \
   && yum clean all
 
 # cross-compiler version