Create Desktop True, Finder bug with yabai workspaces

[aspauldingcode]

Since Create Desktop must be set true, for workspaces to work properly in yabai, we should check if the defaults for create desktop are set false.
Then, we can maybe even suggest to the user to use defaults to set it true, and mention in the manpages that yabai workspaces doesn't work without it true.

In addition, Finder MUST be open. If all instances of Finder are quit, and then NOT reopened, yabai workspaces will mess up again, regardless of Create Desktop is true.
This is because if Finder is not running, the Desktop isn't created.

So, we also need to make sure Finder is actively running.

• Make sure defaults create desktop is true.
• Make sure Finder is running.

Require these by default, so users don't run into workspace issues.
I suggest prompting an error from yabai when it loads, that these need to be set.

References:
#863
#2313