Bump Stan.jl and Jags.jl  to v"0.1.4"

Fix to pass tests if Jags executable or CmdStan are not installed, e.g.
for pkg.julialang.org tests.
Merge pull request #1818 from goedman/metadata-v2

Bump Stan.jl and Jags.jl  to v"0.1.4"