[Doc]Add chinese doc (#10)

### What this PR does / why we need it?
This PR adds Chinese documents for vllm-ascend for Chinese-speaking
developers

### Does this PR introduce _any_ user-facing change?
Change as follows
- add README.zh.md
- add environment.zh.md
- add CONTRIBUTING.zh.md

### How was this patch tested?
By CI

---------

Signed-off-by: wangli <wangli858794774@gmail.com>

README.md

@@ -14,6 +14,10 @@ vLLM Ascend Plugin
 | <a href="https://www.hiascend.com/en/"><b>About Ascend</b></a> | <a href="https://slack.vllm.ai"><b>Developer Slack (#sig-ascend)</b></a> |
 </p>
 
+<p align="center">
+<a ><b>English</b></a> | <a href="README.zh.md"><b>中文</b></a>
+</p>
+
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