Setup Indy SDK build environment for Ubuntu based distro (Ubuntu 16.04)

Install Rust and rustup (https://www.rust-lang.org/install.html).

Install required native libraries and utilities:

apt-get update && \
apt-get install -y \
   build-essential \
   pkg-config \
   cmake \
   libzmq3-dev \
   libssl-dev \
   libsqlite3-dev \
   libsodium-dev

Checkout and build the library:

git checkout https://github.com/hyperledger/indy-sdk.git
cd ./indy-sdk
cargo build

Run integration tests:

Start local nodes pool on 10.0.0.2:9701-9708 with Docker:

docker network create --subnet 10.0.0.0/8 pool_network
docker build -f ci/indy-pool.dockerfile -t indy_pool .
docker run -d --ip="10.0.0.2" --net=pool_network indy_pool

Run tests
```
RUST_TEST_THREADS=1 cargo test
```

See ci/ubuntu.dockerfile for example of Ubuntu based environment creation in Docker.