Moves idpe.QueryService into platform/query.ProxyQueryService
Splits the Request into ProxyRequest and Request.
Changes query.QueryService and query.AsyncQueryService to use a Request
type. This means that the Compiler interface is consumed by the service
to abstract out transpilation vs Flux compilation vs raw spec.
The transpiler handler is removed.
There are separate http handlers and service implementations for each of
the three query services.
Query logging types are moved into platform.
The ResultIterator now expects Cancel to always be called.
The fluxd binary exposes the query endpoint specified in the swagger
file.
Introduces the Statisticser interface which ResultIterators may
implement.
The HTTP implementation uses HTTP trailers to preserve the statistics.
This way we do not need to have all encoders and decoders support
statistics.
This modifies the `MultiResultDecoder` interface to accept an
`io.ReadCloser` so the `ResultIterator` can close the `io.Reader`
instead of doing it through a defer call. It then makes it so the
`Cancel()` method will close the reader or the reader will be
automatically closed when `More()` returns false.