Update rpm spec and systemd unit

contrib/rpm/i2pd.service

@@ -1,16 +1,27 @@
 [Unit]
-Description=I2P router
+Description=I2P Router written in C++
 After=network.target
 
 [Service]
 User=i2pd
 Group=i2pd
+RuntimeDirectory=i2pd
+RuntimeDirectoryMode=0700
 Type=simple
-ExecStart=/usr/bin/i2pd --service
-PIDFile=/var/lib/i2pd/i2pd.pid
-Restart=always
-PrivateTmp=true
+ExecStart=/usr/sbin/i2pd --conf=/etc/i2pd/i2pd.conf --pidfile=/var/run/i2pd/i2pd.pid --logfile=/var/log/i2pd/i2pd.log --daemon --service
+ExecReload=/bin/kill -HUP $MAINPID
+PIDFile=/var/run/i2pd/i2pd.pid
+### Uncomment, if auto restart needed
+#Restart=on-failure
+
+### Use SIGINT for graceful stop daemon.
+# i2pd stops accepting new tunnels and waits ~10 min while old ones do not die.
+KillSignal=SIGINT
+TimeoutStopSec=10m
+
+# If you have problems with hunging i2pd, you can try enable this
+#LimitNOFILE=4096
+PrivateDevices=yes
 
 [Install]
 WantedBy=multi-user.target
-