* Gopkg.lock: use MK v0.10.3
* ooni: stop using legacy GeoIP database files
* Some yak shaving of Makefile
1. remove now broken commands to download deps
2. also define the CXX cross compiler
* chore(dep): migrate from dep to go 1.11+ modules
See https://blog.callr.tech/migrating-from-dep-to-go-1.11-modules/
I need this to simplify my life in building for Travis.
* Introduce build.sh and repair build
In going forward, I believe we don't actually need a Makefile but I
didn't want to make such a radical change now.
* Another strategy wrt gopath
* travis: run regress tests on macOS
Closes#30
This is the command I used:
```
rg 'github.com/openobservatory/gooni' --files-with-matches \
| xargs sed -i '' 's/github.com\/openobservatory\/gooni/github.com\/ooni\/probe-cli/g'
```
