Revert merge of Net.
Merge branch 'master' of https://github.com/kse-jp/RM-3000
Revert "Merge branch 'master' of https://github.com/kse-jp/RM-3000"

This reverts commit 875a84f34da99b5c977b596f3b4db84ba7a1a1a6, reversing
changes made to 3f9cc9861944b09c6d196219257c6960acded422.