Bump piggieback version to 0.1.2
Since version 0.1.0, Piggieback no longer requires an explicit
setup prior to
cemerick.piggieback/cljs-repl (c.f. https://github.com/cemerick/piggieback/blob/c6d1406eb2b21cfa74e53521a293d91641b375c0/CHANGES.md#010
)

This was causing problems while starting a new session with run-node-nrepl
Bump version to 0.1.11