Spawn a host shell instead of a sandboxed `sh` by default

The shell currently defaults to a sandboxed plain `sh`, which is not what most developers want.

It would be cool if it could default to a host-shell (bash, in most cases). I've configured this manually using [host-spawn](https://github.com/1player/host-spawn) and it works really great, since I've done this, I couldn't find any of the annoying bugs that were there before.

More concretely, I've changed in `Settings` → `Tools` → `Terminal` → `Shell Path`:
```
/path/to/host-spawn bash
```

I guess this could also be done by a script inside this wrapper. The binary for host-spawn could be included as well.

This would be a great improvement that I think a lot of people could benefit of.