provide "NaN" and "Infinity" when (de)serializing Java Numbers

Json-P uses this to (de)serialize Double-values to and from Json:

`JsonGenerator write(double value);`

Please provide the ability to (de)serialize "NaN", "+Infinity" and "-Infinity" with any type of Numbers (Double, etc) to produce and consume something like this

```
{
"val1" : "NaN",
"val2" : 1.0,
"val3" : 0.0,
"val4" : "+Infinity"
"val5" : "-Infinity"
}
```

**converter to **produce** json string:**

```
try{
// normal conversion to double
}
catch(NumberFormatException ex){
if(Double.isNaN(val)) return "NaN";
if(Double.isInfinite(val) && val>0) return "Infinity";
if(Double.isInfinite(val) && val<0) return "-Infinity";
}
```

**converter to **consume** "NaN" and "Infinity" from Json-String:**

```
try{
if(val == "NaN") return Double.NaN;
if(val == "Infinity") return Double.POSITIVE_INFINITY;
if(val == "-Infinity") return Double.NEGATIVE_INFINITY;
// normal conversion to double
...
}
```

For example, Json-P could automatically use the `Double`-(de)serializer, if `Double`-Objects are used. If Json-P detects primitive double-types, the `double`-(de)serializer can be used.

Also, Json-P should provide the Json-P configuration property `NAN_AS_STRINGS`:

```
// uses strings for "NaN", "+Infinity", "-Infinity"
// instead of throwing NumberFormatException when (de)serializing
Maps.of(JsonGenerator.WRITE_NAN_AS_STRINGS, true)
```

Actually, Json-P are not able to consume and produce Java Numbers complete: "NaN" and "Infinity" are still valid information about numbers which should not be thrown with exceptions by default.

Related:

- https://github.com/eclipse-ee4j/jsonp/issues/160
- https://github.com/eclipse-ee4j/yasson/issues/306

Start with the JsonGenerator write(double value) API and the requested NAN_AS_STRINGS configuration property. Review the related jsonp-api issue 160 and Yasson issue 306, then establish consistent production and consumption of NaN and signed Infinity values for Java number types; done means the API behavior and configuration are specified and covered for the requested cases.

Written by the indexing model from the issue text.