The make build command only works if you install the dependencies first.
Previously you had to cd into examples/basecoin and run get_vendor_deps
and then cd into cosmos-sdk and then run build.
With this change a user can just run build in the top-level folder and
the dependencies are installed automatically.
If you need to reference things from _attic, please check `ref/attic`.
That branch keeps all the old _attic files.
I've removed it here in order to make it easier for developers to search
and understand the codebase. We shouldn't have stale code on `develop`.
