Add toJson function that does not escape < and >

[m1o1]

Currently, calling toJson on a string that contains < or > will escape them to \u003c and \u003e. I saw this solution on Stack Overflow:

enc := json.NewEncoder(os.Stdout)
enc.SetEscapeHTML(false)

I suspect it would be a breaking change to change toJson to do this, but perhaps there could be another function, toJsonRaw that does not perform this escaping.

[mattfarina]

This would be a breaking change but a new template function that does this would be considered. Pull requests are welcome for new functions.