fix: drop redudant w3 space command for consistency (#57)

We had no output for `w3 space` command resulting in ugly user errors as
mentioned in #44.

This PR addresses it. Simply drop this top level space command.
We do not have one for other ones like `delegation` , `proof`, ...

Closes #44

bin.js

@@ -62,9 +62,6 @@ cli.command('whoami')
   .describe('Print information about the current agent.')
   .action(whoami)
 
-cli.command('space')
-  .describe('Create and mangage w3 spaces')
-
 cli.command('space create [name]')
   .describe('Create a new w3 space')
   .action(createSpace)