doc: Add ai doc translate tool and add English doc. (#1168)

- add tools/doc_translator.py
- translated docs into English

Signed-off-by: longjin <longjin@DragonOS.org>

docs/conf.py

@@ -47,6 +47,7 @@ templates_path = ['_templates']
 # This is also used if you do content translation via gettext catalogs.
 # Usually you set "language" from the command line for these cases.
 language = 'zh_CN'
+locale_dirs = ['locale/']   # path is example but recommended.
 
 # List of patterns, relative to source directory, that match files and
 # directories to ignore when looking for source files.