Remove docs for Layout.{even,odd}, which no longer exist
Remove docs for Layout.{even,odd}, which no longer exist

These attributes were removed in gh-43 (04db4a3e97ea8ba96fd9b947a624a8d8439f60ab), as they were far too large to efficiently store.

We could look at adding them back lazily, but there's little need.
Even if we do eventually do that, we should keep the docs accurate in the meantime.
arsenovic/clifford,arsenovic/clifford