Feature Proposal: Install non-systemd files only

[marillindie]

For non-systemd GNU/Linux users (e.g. Alpine, Artix, Gentoo, Void), it is currently not possible to use this script. However, the function if this script is really useful for timely upgrade. I hereby propose to include a special parameter, e.g. --no-systemd, to support installing and upgrading xray on non-systemd OSes. In this situation, systemd-related files like xray.service should not be generated or installed.

Below is the same message in Chinese.

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上文是下文的英文版本。

非 systemd 用户（如 Alpine，Artix，Gentoo，Void 用户）目前无法使用该脚本，但该脚本的功能有助于及时更新，故期望能添加特殊参数如 --no-systemd 以支持在非 systemd 系统下安装和升级 xray。使用该参数时，无需生成和安装与 systemd 相关的文件，如 xray.service 。