mandelkind on Escape Custom Replacement Keys in ThingHTTP

@Hans: I'm unable to add any additional encoding, since the data is passed by a 3rd party service (IFTTT) - and there is the data already urlEncoded. I suspect ThingHTTP receives the data & urlDecodes it, before sending it along.

So the only solution I can see is that ThingHTTP should ensure it can be passed without any issues.