switch to new registrator and drop CI support for julia 0.7#8

Merged

RalphAS merged 2 commits intoJuliaImages:masterfrom johnnychen94:new-registrator

Apr 28, 2019

+34-18

Commits on Apr 26, 2019

add Project.toml and delete REQUIRE
johnnychen94
committed

Commits on Apr 27, 2019

drop julia v0.7 compatibility
johnnychen94
committed