Fixed IO error for ./data/repos/style.css
Fixed IO error for ./data/repos/style.css

This error is reproduced by running a build with delorean,
deleting the data folder and running a build again. To fix it, we need to check
whether repos folder is present or not in ./data folder.

Change-Id: I013aeccdc481d7f385aada5d790beed39118a0b9

openstack-packages/DLRN,openstack-packages/delorean,openstack-packages/DLRN,openstack-packages/delorean