How can I build [parity](https://github.com/paritytech/parity/releases) as a stable version from source?

```
git clone https://github.com/paritytech/parity
cd parity
cargo build --release

```

gives me 

`version Parity/v1.9.0-unstable-51e6e0b4b-20171230/x86_64-linux-gnu/r‌​ustc1.22.1`

which is unstable and 

```
git checkout tags/v1.7.11

```

gives me this version:

```
version Parity/v1.7.11-unstable-a5ed4cfc4-20171228/x86_64-linux-gnu/‌​rustc1.22.1

```

which is unstable as well. How can I build the stable version from source (latest should be 1.7.11)