Stdweb spawn local future

[izissise]

• Fix not equal assign example
• Rename send_self send_self_batch to send_message send_message_batch
• Use stdweb::spawn_local to execute futures sent to send_future
• Add AgentLinkFuture trait and implementation

Futures successfully executed and sent back message to the Component/Agent using cargo web and asmjs target.
Also tested with wasm32-unknown-unknown target and it work great

Issue: yewstack/yew#776

It depends on yewstack/yew#802 for AgentLinkFuture to work

[hgzimmerman]

Thanks for taking the time to do this!

My only reservation I have about this is discarding web-sys implementation entirely.
There are future plans in Yew to support parallel implementations that rely on either web-sys or stdweb, so the old web-sys based futures support may come in handy later.

Since I can't come up with a scheme that makes feature-gating either stdweb or web-sys support practical right now, I'll resurrect the old implementation myself when it comes time to do so.

Just remove the unneeded dependencies from the cargo.toml and I think that this is good to merge when Yew merges the associated PR there.

[hgzimmerman]

Update, apparently this feature required that experimental_features_which_may_break_on_minor_version_bumps be a feature on stdweb. I'll open another PR to add that.

[izissise]

A damn, I wasn't sure it was needed, sorry about that

[hgzimmerman]

No problem