Support more than 1 sessions

[nicolas-g]

Feature Request: Support the creation of more than 1 sessions.

Right now in a single tmuxp yaml config file, only 1 session seems to be supported. If you define more than one, only the last session will be effective.

Will be nice if we can define more than 1 session in a single file like this:

session_name: Session1
windows:
  - window_name: S1Window1
  - window_name: S1Window2

session_name: Session2
windows:
  - window_name: S2Window1
  - window_name: S2Window2

[joseph-flinn]

@nicolas-g Thanks for your use and interest in tmuxp! And thanks for the feature request. There is/has been a thread with the same request here: #573. All further discussion on this will happen there.