Remove submodules

[nrryuya]

After these branches are merged, submodules need to be removed and written in package.json as a dependent modules.

• remix-ide
  • https://github.com/ethereum/remix-ide/pull/1536
• remixd
  • https://github.com/jacqueswww/vyper/blob/add_cors_all_headers/bin/vyper-serve#L92
  • https://github.com/ethereum/remixd/pull/58

[nrryuya]

Remove submodules when these branches are merged https://github.com/ethereum/remix-ide/pull/1536 https://github.com/ethereum/vyper/pull/1041