This commit adds a new chain-based, interception contract to be used
with `WebClient`. This is the HTTP client equivalent of the `WebFilter`
contract already implemented in web reactive server.

A `ClientHttpRequestInterceptor` implementation can transform the
outgoing HTTP request (method, URI or headers) before delegating it to
the next interceptor in the chain, or bypass the request processing
altogether and return a (cached) HTTP response.

Issue: SPR-14502

This commit also removes the ServerHttpResponse parameter, not
needed here since it is possible to override the write() method.

Issue: SPR-14557

This commit handles range requests in `ResourceWebHandler`, using the
`ResourceHttpMessageWriter` configured within the handler.

This `WebHandler` will add a `HTTP_RANGE_REQUEST_HINT` writer hint
containing all the HTTP Range information of the request.

Issue: SPR-14664

This new `HttpMessageWriter` leverages the `ResourceRegionEncoder` to
write `ResourceRegion` to HTTP responses, thus supporting HTTP Range
requests.

Whenever possible, this message writer uses the zero copy support for
single range requests.

This `HttpMessageWriter` is never used directly, but is used as a
delegate by the `ResourceHttpMessageWriter`. When provided with the
`BOUNDARY_STRING_HINT`, the `ResourceRegionHttpMessageWriter`
adapts its behavior in order to write a single/multiple byte ranges.

Issue: SPR-14664

This commit adds the necessary infrastructure for the support of HTTP
Range requests. The new `ResourceRegionEncoder` can write
`ResourceRegion` objects as streams of bytes.

The `ResourceRegionEncoder` relies on an encoding hint
`BOUNDARY_STRING_HINT`. If present, the encoder infers that multiple
`ResourceRegion`s should be encoded and that the provided boundary
String should be used to separate ranges by mime boundaries.
If that hint is absent, only a single resource region is encoded.

Issue: SPR-14664

This commit makes it possible, in addition to provide hints, to
perform additional operations with the request and the response
at ServerHttpMessageReader/Writer level.

AbstractServerHttpMessageReader/Writer now provide
convenient beforeRead/beforeWrite abstract methods for such need.

Issue: SPR-14557

Issue: SPR-14557

Issue: SPR-14735

Resetting the connection first before invoking a failure callback on
the application handler ensures that any checks to isConnected will
return false.

Issue: SPR-14721

* pr/1180:
  Polish
  Documentation formatting fix

Removed unnecessary quotation marks that caused improper rendering
of in-line code.

Closes gh-1180

* pr/1181:
  Add missing quotation mark

Closes gh-1181

Issue: SPR-14728

Issue: SPR-14729
(cherry picked from commit ca17edd5)

This commit overrides the `checkResource` implementation in
`ScriptTemplateView` in order to check if the template file resource is
available and if the resolver can then proceed with rendering the
template.

Issue: SPR-14729
Cherry-picked from: 66b370e1

In order to simplify configuration for use cases involving @Bean where
only a bean name or aliases are supplied as an attribute, this commit
introduces a new 'value' attribute that is an @AliasFor 'name' in @Bean.

Issue: SPR-14728

Refactor BodyInsertor to expose insertion logic directly, rather than
exposing a writer function and supplier.

Fixed package tangle between w.r.f.RequestPredicates and w.r.f.support.RequestWrapper.

Issue: SPR-14538

Issue: SPR-14682