Fedora 27 : singularity (2018-abe4d2383e)

This is a straightforward update from 2.5.1 to the newly-released 2.5.2. Release notes are here : https://github.com/singularityware/singularity/releases/tag/2.5.2 The most important fix is a security issue in the overlay code. Please look for regressions in your Singularity runtime workflows. No...