JSON instruction parsing on node process fails for large instructions

[tpetry]

In my first tests everything was working correctly and rialto seemed like a nice solution. But after implementing everything, I encountered a strange bug which took a long to debug: Sending large instructions (10KB or 100KB) fails with the nodejs part throwing an error because of malformed JSON instructions. With small instructions, everything is working correctly.

I was able to pin-down the exact issue: When sending results from nodejs to php a chunked protocol is used. But it is not used when sending data from php to nodejs. The nodejs logic expects the instruction to be read in one single receive statement:

rialto/src/node-process/Connection.js

Lines 46 to 50 in 1e994b8

	socket.on('data', data => {
	this.emit('activity');
	this.handleSocketData(data);
	});

But with large instructions like sending large html documents this is not possible, there will be packet fragmentation. Chunking needs to be done on both ways.

[lacieri]

This is a duplicate of #87