Something seems strange with your registry. Can you try to remove .julia/registries
and try again.
This is what I get:
(v0.7) pkg> add https://github.com/fredrikekre/ImportMacros.jl
Updating git-repo `https://github.com/fredrikekre/ImportMacros.jl`
┌ Warning: packages will require to have a [Julia]Project.toml file in the future
└ @ Pkg.Types Types.jl:814
[ Info: Assigning UUID 7c456fe6-5f30-11e8-3ace-f50c1f4cee28 to ImportMacros
Updating registry at `~/.julia/registries/Uncurated`
Updating git-repo `https://github.com/JuliaRegistries/Uncurated.git`
Resolving package versions...
Downloaded MacroTools ─ v0.4.0
Updating `~/.julia/environments/v0.7/Project.toml`
[7c456fe6] + ImportMacros v0.0.0 # [https://github.com/fredrikekre/ImportMacros.jl]
Updating `~/.julia/environments/v0.7/Manifest.toml`
[7c456fe6] + ImportMacros v0.0.0 # [https://github.com/fredrikekre/ImportMacros.jl]
[1914dd2f] + MacroTools v0.4.0