Reorg src folders to services/*/*.jl

[dehann]

I'd recommend we have folder structure:

src/services/A/a.jl
src/services/B/b.jl

rather than the current:

src/services/*.jl
src/A/services/a.jl
src/B/services/b.jl

[dehann]

This is going to change with new plan on introducing more subprojects, deferring.