Add parachains for rococo (#144)

* Add parachains for rococo

* Fix chain specs

* Update to revert log rotation

* Support selecting the chain in `export-genesis-state`

* Add subcommand for exporting the genesis wasm of a Parachain

* Update stuff

* Fix `export-genesis-wasm`

* Update the polkadot ref

* Add bootNodes address

* Add bootNodes address - track

* Add bootNodes address - trick

* Fix incorrect peer id (trick)

* Fixes https://github.com/paritytech/cumulus/issues/157

* Update chainspecs

* Update specs again

* Set correct sudo account

* Update properties

* Update readme

* Update `Cargo.lock`

* Switch to rococo-branch

Co-authored-by: Evaldo <[email protected]>
Co-authored-by: Cecile Tonglet <[email protected]>