fix: Initialize log file permissions

1. It seems that someone will run V2Ray directly through commands instead of systemd first, which will cause wrong Log file permissions and affect subsequent systemd operations.

issue #38

install-release.sh

@@ -370,8 +370,12 @@ install_v2ray() {
     if [[ ! -d '/var/log/v2ray/' ]]; then
         if [[ -n "$(id nobody | grep nogroup)" ]]; then
             install -d -m 700 -o nobody -g nogroup /var/log/v2ray/
+            install -m 600 -o nobody -g nogroup /var/log/v2ray/access.log
+            install -m 600 -o nobody -g nogroup /var/log/v2ray/error.log
         else
             install -d -m 700 -o nobody -g nobody /var/log/v2ray/
+            install -m 600 -o nobody -g nobody /var/log/v2ray/access.log
+            install -m 600 -o nobody -g nobody /var/log/v2ray/error.log
         fi
         LOG='1'
     fi