align "set" on fl[oa]r "set"

for example:

``` ruby
    it 'sequences its children' do

      rad = %{
        set a
          0
          1
      }

      r = @executor.launch(rad)

      expect(r['point']).to eq('terminated')
      expect(r['from']).to eq('0')
      expect(r['payload']).to eq({ 'a' => 1, 'ret' => 1 })
    end
```
