pure php grpc

[ZhouyihaiDing]

Try to implement gRPC with pure PHP.
Use curl to send and receive rpc with http2_prior_knowledge.

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[ZhouyihaiDing]

Do we re-use the plugin from grpc-php(C-core)? Generated Client doesn't have the default value for it. Something like credentials must be set at the second parameter.

[ZhouyihaiDing]

if => while
or add
if($active<=0) break; to line 137 because curl_multi_select is blocked until activity or timeout. If there are no more activity with valid $this->received_data, every yield will wait for a time-out time.

[fengli79]

Let's skip the example code for now. As we probably want to use the same proto defined in grpc report instead of using echo.prot here.

[ZhouyihaiDing]

All example related files are removed.

[fengli79]

Move this to /src/Grpc folder. The dir structure would be something like:
/src
/test
/doc
...