• Standardize platform names, refer to
  https://pyarmor.readthedocs.io/en/v5.7.5/platforms.html#standard-platform-names
• Run obfuscated scripts in multiple platforms, refer to
  https://pyarmor.readthedocs.io/en/v5.7.5/advanced.html#running-obfuscated-scripts-in-multiple-platforms
• Downloaded dynamic library files by command command will be saved in the
  ~/.pyarmor/platforms other than the installed path of pyarmor package.
• Refine platforms folder structure according to new standard platform name
• In command obfuscate, build, runtime, specify the option --platform
  multiple times, so that the obfuscated scripts could run in these platforms