Removing bar connecting grouped staves

[Gilberto Agostinho]

Hi everyone,

I am trying to create a diagram using Lilypond and I would like to 
remove the vertical bar connecting a series of grouped staves. This is 
the bar that is in the left hand side of a score and runs through all 
staves, and where instrument names are normally written. Would it be 
possible to hide it somehow?

Below is a minimal example:

\version "2.19.82"
\score {
    <<
        \new Staff {c'4 d' e' f'}
        \new Staff {c'4. d'4. e'4}
        \new Staff {c'2 d'2}
    >>
    \layout{
        \omit Score.BarLine
    }
}

https://i.postimg.cc/W3krqyTF/line.png

The diagram I am creating has a complex rhythm and I am using a group of 
staves so that the rhythm of each line matches the one above, which is 
why I am trying to use this trick of grouping them and then hiding the 
connecting bar.

Many thanks,
Gilberto