Docker file fixes

Hi,

these are small fixes to the docker image building file. Mainly concerning the XercesC build from source rather than from the package directory. The changes are necessary to ease the image in GeoModelATLAS

CI/DockerfileBase

@@ -6,6 +6,9 @@ FROM  ubuntu:20.04
 
 USER root
 WORKDIR /root
+
+ARG XercesC_VERSION=3.2.3
+
 ENV DEBIAN_FRONTEND noninteractive
 
 ### Install tzdata package
@@ -15,7 +18,7 @@ ENV DEBIAN_FRONTEND noninteractive
 RUN apt-get update && apt-get install -y tzdata && ln -fs /usr/share/zoneinfo/America/New_York /etc/localtime && dpkg-reconfigure --frontend noninteractive tzdata
 
 ### Install C++, cmake and python
-RUN apt-get update && apt-get install -y cmake g++ python git sudo nano
+RUN apt-get update && apt-get install -y cmake g++ python git sudo nano wget
 
 ### Boost installation
 RUN apt-get update && apt-get install -y libboost-all-dev
@@ -27,7 +30,19 @@ RUN  apt-get update &&  apt-get install -y qt5-default qt5-qmake qtbase5-dev-too
 RUN apt-get update && apt-get install -y sqlite3 libsqlite3-dev
 
 ### Install eigen to avoid the own installation
-RUN apt-get update && apt-get install -y libeigen3-dev libxerces-c-dev
+RUN apt-get update && apt-get install -y libeigen3-dev 
+
+### Another layer of building xer
+RUN wget https://cern.ch/lcgpackages/tarFiles/sources/xerces-c-${XercesC_VERSION}.tar.gz && \
+         tar -xzf xerces-c-${XercesC_VERSION}.tar.gz && \
+         mkdir build && \
+         cd build && \
+         cmake ../xerces-c-${XercesC_VERSION} && \
+         make -j2  && \
+         make install && \
+         cd .. && \
+         rm -rf xerces-c-${XercesC_VERSION} build
+
 
 ### Last but very important, the installation of the OpenGL module
 RUN apt-get update && apt-get install -y mesa-utils build-essential libgl1-mesa-dev