loongson/pypi: links for lib4vex

loongson/mirror lib4vex-0.2.1-py2.py3-none-any.whl
loongson/mirror lib4vex-0.2.0-py2.py3-none-any.whl
loongson/mirror lib4vex-0.1.0-py2.py3-none-any.whl