Add iced-runtime dependency

While following the readme I received the following error:
```bash
$ icake build

/Users/jareddeckard/Github/warpwallet/Cakefile:661
          throw err;
                ^
Error: module "iced-runtime" not found from "/Users/jareddeckard/Github/warpwallet/src/iced/top.iced"
```

It seems that I just needed to install ```iced-runtime```.