JSON output writer

[WyriHaximus]

Implements / Closes #24
Closes #29

TODO:

• Extract echoing output into an EchoWriter
• JsonWriter
• --json flag

[coveralls]

Coverage remained the same at 100.0% when pulling 799b4fb on WyriHaximus-labs:json-writer into 33e6587 on Brunty:master.

[coveralls]

Coverage remained the same at 100.0% when pulling 799b4fb on WyriHaximus-labs:json-writer into 33e6587 on Brunty:master.

[coveralls]

Coverage remained the same at 100.0% when pulling af93564 on WyriHaximus-labs:json-writer into 33e6587 on Brunty:master.

[WyriHaximus]

@Brunty this PR is now ready for review. It currently outputs a line of JSON per result/error/stats. Changing it to do it in one big JSON object would have meant a bigger change. Up to you if you prefer it per line or one big JSON object. Example output:

[Brunty]

Hmm, I'll give it some thought, will look at the pros / cons of each - depends on use case, one big object would make it easier to parse / use in another tool for working with the output.

Also wondering about the possibility of a pretty print flag too, not useful for machines, but useful for people perhaps? Using JSON_PRETTY_PRINT in json_encode() http://php.net/manual/en/function.json-encode.php - thoughts? (it's just something I've come across in other tools before, it's handy to not have to rely on having another tool such as piping it to | python -m json.tool

[WyriHaximus]

Hmmm the JSON_PRETTY_PRINT sounds like a good idea, but that will only work on one big object. You know what, I'll file another PR building on that one doing one big object so you can compare both.

[Brunty]

@WyriHaximus - cool, if there's anything I can help with let me know. I've got some downtime today so I'm going to take a look at this PR. Thanks for the work once again <3

[WyriHaximus]

@Brunty #29 is up 😎