use wkhtml2pdf instead of weasyprint, use CentOS

Author: PhilippSalvisberg

docker/Dockerfile

@@ -1,34 +1,23 @@
-FROM ubuntu:18.04
+FROM centos:7.5.1804
 
 LABEL maintainer="philipp.salvisberg@trivadis.com"
 LABEL description="Tools to generate website, pdf and ebook using Materials for MkDocs."
 LABEL build.command="docker build . --tag trivadis/mktools:latest"
 
-RUN apt-get update 
-RUN apt-get upgrade -y
-RUN apt-get install -y build-essential \
-                       python3-dev \
-                       python3-pip \
-                       python3-setuptools \
-                       python3-wheel \
-                       python3-cffi \
-                       libcairo2 \
-                       libpango-1.0-0 \
-                       libpangocairo-1.0-0 \
-                       libgdk-pixbuf2.0-0 \
-                       libffi-dev \
-                       shared-mime-info
-RUN apt-get install -y git
-RUN pip3 install --upgrade pip
-RUN pip3 install mkdocs \
-                 mkdocs-material \
-                 mkdocs-awesome-pages-plugin \
-                 pymdown-extensions \
-                 mike \
-                 weasyprint 
+RUN yum install -y https://centos7.iuscommunity.org/ius-release.rpm
+RUN yum update -y
+RUN yum install -y python36u python36u-libs python36u-devel python36u-pip
+RUN yum install -y git
+RUN yum install -y https://github.com/wkhtmltopdf/wkhtmltopdf/releases/download/0.12.5/wkhtmltox-0.12.5-1.centos7.x86_64.rpm
+RUN pip3.6 install --upgrade pip
+RUN pip3.6 install mkdocs \
+                   mkdocs-material \
+                   mkdocs-awesome-pages-plugin \
+                   pymdown-extensions \
+                   mike 
 
-ENV LC_ALL=C.UTF-8
-ENV LANG=C.UTF-8
+ENV LC_ALL=en_US.utf8
+ENV LANG=en_US.utf8
 
 # volume for GitHub project's root folder containing docs folder  
 RUN mkdir /data