Create option to hide command log header

[strboul]

Is your feature request related to a problem? Please describe. I'd like to keep the command log visible in the panes but I don't need to see the header text all the time as I know how to hide/focus the panel.

┌─Command Log──────────────────────────────────
│You can hide/focus this panel by pressing '@'
│

Describe the solution you'd like It'd be nice to have a config option to hide the header text.

Proposed option name:

gui:
  showCommandLogHeader: false

(Somewhere here needs a config conditional.)

Describe alternatives you've considered

gui.showCommandLog: false hides the whole command log which I don't prefer. There needs to be a new option just to remove that sticky header.