Drop + from hal+json and hal+xml for routing file extension.

[cnizzardini]

Drop + from hal+json and hal+xml for routing file extension. If a user wants to enable routing by extension, then I think having the plus in there is quite odd. In the absence of a standard on this I think this is fair.

See original PR #14867

[ADmad]

Are such URL extensions normally used? I would expect the URL to be .json/.xml only.

[cnizzardini]

Its unlikely, but I don't see the harm in providing the option.

[ADmad]

Well adding things which aren't normally used increases unnecessary bloat.

[othercorey]

I am ok with this since it looks like other types. Is there any code or framework that actually uses hal that we could ask about this for consistency? Someone else must be using this as a standard over us. Can we ask the owner of the type in the spec?

[cnizzardini]

Not to my knowledge, symfony api platform does allow routes by .jsonld in their demo here https://demo.api-platform.com/, but when I try with .haljson its a no-go.

[cnizzardini]

We're decreasing bloat by removing two characters ;-)

[markstory]

Having the + makes URL generation tricky as + also overlaps with the URL encoded space.