Release 4.8 Remove Guava dependency. New HtmlFlow.ViewFactory.Builder and Hot views.

This release removes the Guava dependency, previously used only for HTML text escaping, and replaces it with the original HTML escaping source code.

It also introduces ViewFactory.Builder, allowing configuration of HtmlView parameters, such as isIndented, threadSafe and preEncoding.

Finally, it adds a new type of Hot view that recalculates all HTML—including static HTML blocks— on each rendering, which is useful for http4k integration with hot-reload support.