Add Http2 flags for advanced configurations

[allada]

Some users will want to tune advanced http2 configurations. This PR gives that ability.

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This change is 

[allada]

+@blakehatch

Reviewable status: 0 of 3 files reviewed, all discussions resolved (waiting on @blakehatch)

[blakehatch]

Reviewed 3 of 3 files at r1, all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @allada)

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cas/cas_main.rs line 467 at r1 (raw file):

        if let Some(value) = http_config.http2_max_header_list_size {
            http.http2_max_header_list_size(value);
        }

Would just need another case for the http2_only method here if adding it is of interest.

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config/cas_server.rs line 212 at r1 (raw file):

/// specified.
#[derive(Deserialize, Debug, Default)]
pub struct HttpServerConfig {

https://docs.rs/hyper/latest/hyper/server/conn/struct.Http.html#method.http2_only

Only method in the crate not currently supported by this config is http2_only, not necessary for feature completeness here but restricting to just http2 could maybe have it's uses.

[allada]

Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @blakehatch)

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cas/cas_main.rs line 467 at r1 (raw file):

Previously, blakehatch (Blake Hatch) wrote…

Would just need another case for the http2_only method here if adding it is of interest.

I thought about it, but decided that it's unlikely to ever be used.

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config/cas_server.rs line 212 at r1 (raw file):

Previously, blakehatch (Blake Hatch) wrote…

https://docs.rs/hyper/latest/hyper/server/conn/struct.Http.html#method.http2_only

Only method in the crate not currently supported by this config is http2_only, not necessary for feature completeness here but restricting to just http2 could maybe have it's uses.

(see above)

[blakehatch]

Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @allada)

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cas/cas_main.rs line 467 at r1 (raw file):

Previously, allada (Nathan (Blaise) Bruer) wrote…

I thought about it, but decided that it's unlikely to ever be used.

Done

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config/cas_server.rs line 212 at r1 (raw file):

Previously, allada (Nathan (Blaise) Bruer) wrote…

(see above)

Done

[blakehatch]

Done

Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @allada)