Add OperationError error type

[d98762625]

Add OperationError Error type and use for errors to be printed to the output panel

Why

In issue #287 I mentioned error handling behaviour and the need for Operations to throw errors. This is so in the api we can catch them and return them in the expected format (in a promise .catch, for example).

This PR lays the ground work for that by introducing an OperationError class, which is thrown whenever an operation caught an error and printed the message as the output. The Recipe now handles the error catching and printing, but only if it is of this new OperationError class.

There was enough work here for it to be a standalone PR. Plus, I think it's best to introduce this error class ASAP so we can use it in the other operations as we move them over to module format. I have converted all current non-legacy operations to use this new method, but I assume others will need to use it too.

Expected behaviour change

None

Notes

• I have left the RawInflate operation error uncaught, as it was never caught and printed originally. This was the only other currently-converted class that had throw in it.
• The new babel-plugin-transform-builtin-extend library is necessary for babel to recognise extends from native JS types. Otherwise instanceof OperationError doesn't work.

[d98762625]

@n1474335 I would appreciate your feedback, especially around making sure I haven't missed anything in the Recipe flow

[n1474335]

This looks great, I'll merge it now. Remember to add the author, copyright and license in the top level comment for new files.

I like how this works well with the progress indicator so that operations that error get highlighted in red.