Final tweaks for PoC-2 runtime upgrade (#348)

* Final tweaks for PoC-2 runtime upgrade

* Address grumble

* Avoid slow wasm

* New poc-2-era bootnodes

* Fix warning

* Typo

* Fix for allocation in wasm

* Fix & runtimes.

* PoC-1 should be default.

* Name testnet Krumme Lanke, update README

* YML update

* Use the right port