'Echos parameters as JSON (debugging).
Attempts to parse values passed as boolean, float, then int. Defaults
to string. Non-recursive (will not parse lists).'

@web.json
def echo_json(self, trans, **kwd):

    rval = {}
    for k in kwd:
        rval[k] = kwd[k]
        try:
            if (rval[k] in ['true', 'True', 'false', 'False']):
                rval[k] = string_as_bool(rval[k])
            rval[k] = float(rval[k])
            rval[k] = int(rval[k])
        except:
            pass
    return rval
