Add biblatex, biber and index to the docker image

.CI/Jenkinsfile

@@ -18,7 +18,7 @@ pipeline {
   stage('build') {
     agent {
       docker {
-        image 'modelicaspec/latexml:20201119'
+        image 'modelicaspec/latexml:20201130'
         label 'linux'
         alwaysPull true
       }
@@ -74,7 +74,7 @@ pipeline {
           buildingTag()
           anyOf {
             branch 'master'
-            branch 'maint/**'                
+            branch 'maint/**'
           }
         }
       }

.CI/latexml/Dockerfile

@@ -23,7 +23,7 @@ RUN sed -i s,http://archive.ubuntu.com/ubuntu/,mirror://mirrors.ubuntu.com/mirro
  && $INSTALL/install-tl --profile texlive.profile \
  && rm texlive.profile \
  && tlmgr update --self --all --reinstall-forcibly-removed \
- && tlmgr install latexmk listings caption cleveref xcolor float multirow tocloft parskip etoolbox \
+ && tlmgr install latexmk listings caption cleveref xcolor float multirow tocloft parskip etoolbox index biblatex biber \
  && cpanm JSON \
  && cpanm LaTeXML \
  && apt-get autoremove -qy make gcc curl wget git cpanminus libxml2-dev libxslt-dev \

.CI/latexml/Dockerfile.2.incremental

@@ -0,0 +1,5 @@
+FROM modelicaspec/latexml:20201119
+
+RUN tlmgr update --self \
+ && tlmgr install index biblatex biber \
+ && apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/ /root/.cpanm/work*