it's not conflicted with shadowsocks-python now. users can install both python and libev
ports of shaowsocks now. but they should migrate their old configuration file from
/etc/shadowsocks/config.json to /etc/shadowsocks-libev/config.json
Note:
Debian/Ubuntu users may have to `sudo rm -f /etc/shadowsocks` before install
the new `shadowsocks-libev` package.
For library user, the pkg-config package is renamed to `shadowsocks-libev` but
the library name is still the `libshadowsocks` (use `-lshadowsocks` to link)