CLI: refactoring: remove Options from sc_service::Configuration's fields

[cecton]

Major changes

1. Removes VersionInfo and replace by a trait SubstrateCli that needs to be implemented on the top level structopt of the binary
2. Add a proc_macro spec_factory to put on a spec factory/load spec function to help the impl of SubstrateCli (will automatically fill version, executable name, etc... for you)
3. Remove Option on sc_service::Configuration's fields where it doesn't make any sense.
4. Add a trait CliConfiguration that needs to be implemented on structopts that are considered as commands (subcommands and runcmd). This these impl are all provided by sc_cli by default but if the user add a subcommand, they will need to implement it.
5. Add a proc_macro substrate_cli_params to help impl the CliConfiguration
6. Replaced impl_version by full version and dropped Configuration.full_version()

Minor changes

5. Merge Configuration.node and NetworkConfiguration.node_name because they are the same thing
6. Removed config_path in NetworkConfiguration because it's not used and it's redundant with net_config_path
7. Re-export NoExtension and TracingReceiver in sc_service
8. Added a default impl for WasmExecutionMethod to Intepreted
9. Renamed "role" to "roles" because you can be an authority and a full node
10. ... (more details will follow)

Help needed

Please check and propose fixes for all the new documentation.

Closes #4776

polkadot companion: paritytech/polkadot#935

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