Publish comline-runtime to crates.io (1.0 requirement), and the no-network rule #115

Part of ComlineProject/core#227. Proposal: ComlineProject/docs#163, proposals/offline/supply.md#generated-codes-dependencies.

• 1.0 requirement: publish comline-runtime to crates.io, so generated code names a version instead of a git rev, and cargo vendor and registry mirrors work as usual. Related: Reserve package names on crates.io and npm docs#102 (reserve names).
• Until then: document vendoring for sealed builds (cargo vendor handles git dependencies).
• Standing rule: the runtime never reaches anything but the peer it is given. State it and keep it tested.