Add Option until / before to Gantt Diagram

[RoyiAvital]

Is your feature request related to a problem? Please describe.
I'd like to set the end of a task by another task / milestone.

Describe the solution you'd like
Just like one could set the beginning of a task by after <taskName> I want to be able to end it by before <taskName> or until <taskName>.
It should also support milestones.

Describe alternatives you've considered
Specify the date explicitly.

[RufusJWB]

@RoyiAvital Did you perform a "Triage" on this issue? I'd love to have this feature

[RoyiAvital]

@RufusJWB , I am not a developer. I am just a user suggesting a feature I'd love to have and use.

[RufusJWB]

@RufusJWB , I am not a developer. I am just a user suggesting a feature I'd love to have and use.

I assumed you to be the maintainer :-)