refactoring out consistency0 as a variable called reposerver

Hi Simon, For SecureHPC I need to clone consistency0 to be accessible from an internal network. Therefore I am making the hostname and IP of consistency0 a variable in ansible cluster in a box. Then for my /vars ( aka cluster-configuration ) I just have to change variables not roles.

The testpipeline which executes this role is all green. https://gitlab.erc.monash.edu.au/hpc-team/ansible_cluster_in_a_box/pipelines/9172