Modify yum repository base URLs to point to CERN's mirror

Fixes #87

.dockerignore

@@ -1 +1,2 @@
 *
+!configs/docker

Dockerfile

@@ -2,6 +2,9 @@ FROM jalle19/centos7-stlinux24
 
 WORKDIR /build
 
+# Use CERN mirror, everything official has been shut down long ago
+COPY ./configs/docker/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo
+
 RUN yum -y update && \
   yum -y install epel-release && \
   yum -y install wget make gcc git python wget tar \

configs/docker/CentOS-Base.repo

@@ -0,0 +1,43 @@
+# CentOS-Base.repo
+#
+# The mirror system uses the connecting IP address of the client and the
+# update status of each mirror to pick mirrors that are updated to and
+# geographically close to the client.  You should use this for CentOS updates
+# unless you are manually picking other mirrors.
+#
+# If the mirrorlist= does not work for you, as a fall back you can try the 
+# remarked out baseurl= line instead.
+#
+#
+
+[base]
+name=CentOS-$releasever - Base
+#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os&infra=$infra
+baseurl=http://linuxsoft.cern.ch/centos-vault/centos/$releasever/os/$basearch/
+gpgcheck=1
+gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
+
+#released updates 
+[updates]
+name=CentOS-$releasever - Updates
+#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates&infra=$infra
+baseurl=http://linuxsoft.cern.ch/centos-vault/centos/$releasever/updates/$basearch/
+gpgcheck=1
+gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
+
+#additional packages that may be useful
+[extras]
+name=CentOS-$releasever - Extras
+#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras&infra=$infra
+baseurl=http://linuxsoft.cern.ch/centos-vault/centos/$releasever/extras/$basearch/
+gpgcheck=1
+gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
+
+#additional packages that extend functionality of existing packages
+[centosplus]
+name=CentOS-$releasever - Plus
+#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=centosplus&infra=$infra
+baseurl=http://linuxsoft.cern.ch/centos-vault/centos/$releasever/centosplus/$basearch/
+gpgcheck=1
+enabled=0
+gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7