Integrate aria2c support & fix unintended behavior for docker image (#1073)

* Update Dockerfile

* Create docker-bootstrap.sh

In addition to spawn cloudreve, this script generates password for aria2 so that users can take advantage of aria2 more conveniently instead of configuring aria2 by themselves.

docker-bootstrap.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+GREEN='\033[0;32m'
+RESET='\033[0m'
+if [ ! -f /etc/cloudreve/aria2c.conf ]; then
+    echo -e "[${GREEN}aria2c${RESET}] aria2c config not found. Generating..."
+    secret=$(tr -dc A-Za-z0-9 </dev/urandom | head -c 13)
+    echo -e "[${GREEN}aria2c${RESET}] Generated port: 6800, secret: $secret"
+    cat <<EOF > /etc/cloudreve/aria2c.conf
+enable-rpc=true
+rpc-listen-port=6800
+rpc-secret=$secret
+EOF
+fi
+aria2c --conf-path /etc/cloudreve/aria2c.conf -D
+cloudreve