fix(whl): opt whl version

example:
1:export PUBLIC_VERSION_POSTFIX=rc1 for create a rc1 version
2:export PUBLIC_VERSION_POSTFIX=dev20210225 for create daily version
3:export PUBLIC_VERSION_POSTFIX=rc1.dev20210225 and export LOCAL_VERSION=mc40 for create special version
GitOrigin-RevId: 8caa7646d0ca6f6d7b91081b2a68a21a75ccab9e

imperative/python/setup.py

@@ -47,11 +47,19 @@ with open("megengine/version.py") as fp:
 __version__ = v['__version__']
 
 email = 'megengine@megvii.com'
-local_version = os.environ.get('LOCAL_VERSION')
-if local_version:
-    __version__ = '{}{}'.format(__version__, local_version)
+# https://www.python.org/dev/peps/pep-0440
+# Public version identifiers: [N!]N(.N)*[{a|b|rc}N][.postN][.devN]
+# PUBLIC_VERSION_POSTFIX use to handle rc or dev info
+public_version_postfix = os.environ.get('PUBLIC_VERSION_POSTFIX')
+if public_version_postfix:
+    __version__ = '{}{}'.format(__version__, public_version_postfix)
 sdk_name = os.environ.get('SDK_NAME', 'cpu')
 __version__ = '{}+{}'.format(__version__, sdk_name)
+# Local version identifiers: <public version identifier>[+<local version label>]
+# reserved for special whl package
+local_version = os.environ.get('LOCAL_VERSION')
+if local_version:
+    __version__ = '{}.{}'.format(__version__, local_version)
 
 packages = find_packages(exclude=['test'])
 megengine_data = [

scripts/whl/BUILD_PYTHON_WHL_README.md

@@ -72,7 +72,7 @@ export TENSORRT_ROOT_DIR=/path/to/tensorrt
 ALL_PYTHON="36m" ./scripts/whl/manylinux2014/build_wheel_common.sh -sdk cu101
 ```
 
-* If you just want to build with cpu only version, you can set `BUILD_WHL_CPU_ONLY` environment 'ON'. eg:
+* If you just want to build with cpu only version, you can set `-sdk` environment 'cpu'. eg:
 ```bash
 ALL_PYTHON="36m" ./scripts/whl/manylinux2014/build_wheel_common.sh -sdk cpu
 ```

scripts/whl/manylinux2014/build_wheel_common.sh

@@ -199,6 +199,7 @@ fi
 
 docker run --rm -it $TMPFS_ARGS \
     -e UID=${USERID} \
+    -e PUBLIC_VERSION_POSTFIX=${PUBLIC_VERSION_POSTFIX} \
     -e LOCAL_VERSION=${LOCAL_VERSION} \
     -e BUILD_WHL_CPU_ONLY=${BUILD_WHL_CPU_ONLY} \
     -e ALL_PYTHON="${ALL_PYTHON}" \