Add Text Encoding Brute Force operation

[Cynser]

Closes #423.

Made a simple operation that just runs through all the charsets and encodes the input with each. Added a test for it as well.

[n1474335]

This looks great, thanks.

Mojibake is often a result of text being encoded into the wrong encoding, so the solution is to decode, rather then encode. It would be useful if this operation listed all possible decodings as well as encoding, in case it shows something useful.

[Cynser]

Thanks - I've added a decode option.

Needed to add the try-catch, as some inputs were causing an 'Unrecognized code' error when it wasn't possible to decode with that encoding, causing the whole operation to fail. Not sure if there's a better way of doing that.

[n1474335]

Fantastic, thanks. I've updated this a little to use Array.forEach instead of the for loop as I think it looks a little neater. I've also modified the output a little. The operation now returns a JSON list of possible encodings. When it is displayed in the web app, there is a presentation layer on top of this which displays it as an HTML table. This makes things line up a little nicer.