* feat: add warning message when the local node is offline for remote pinning
* feat: check is node is online
* feat: add test in t0700-remotepin.sh
* feat: use grep and fix the test
* fix: print to stdout only when --enc=text
This ensures we don't break JSON produced by --enc=json
Co-authored-by: Marcin Rataj <lidel@lidel.org>