Reloading Oni via quick command with multiple windows causes oni split mode

[akinsho]

When using oni with multiple windows reloading one causes the newly reloaded oni session to blend with the first.

Steps to reproduce hopefully:

1. Open an Oni window,
2. Open a second oni window
3. Select reload Oni in one window via Command palette

Outcome:

Oni attempts to reload the second window inside the first which opens as an oni split (the [WIP] oni split mode) but with duplicated sidebars.

Possible Cause:

The reload oni command in the CommandPalette has a reference to the first oni instance always so requesting a reload acts the same as trying to open a second oni instance which somehow triggers the code for the Oni split mode.

[akinsho]

Seems to have been fixed by changes made in #1747