Describe the bug
Spaces in route parameters are encoded as plus signs.

To Reproduce

    @Test
    public void spacesInRouteParamArePercentEncoded() {
        HttpRequest<?> request = Unirest.get("https://en.wikipedia.org/wiki/{pageName}")
                .routeParam("pageName", "Mosaics of Delos");
        System.out.println(request.getUrl());
        Assertions.assertTrue(request.asEmpty().isSuccess());
    }

Expected behavior
Spaces in route parameters must be encoded as %20 sequence.

Screenshots
Not applicable.

Environmental Data:

• Java 1.8
• Unirest 3.4.00

Additional context
The unirest uses URLEncoder class to encode route parameters, but it should be used for HTML form encoding, not for path encoding.