fix syntax error in aria2c.sh (#230)

* fix syntax error in aria2c.sh

* fix syntax error

aria2c.sh

@@ -1,10 +1,10 @@
-#! /bin/bash -euo
+#! /bin/bash -eu
 
 sed -i 's/6800/'"${ARIA2_EXTERNAL_PORT}"'/g' /usr/local/www/aria2/js/aria-ng*.js
 RPC_SECRET_BASE64=$(echo -n ${RPC_SECRET} | base64)
 sed -i 's/secret:\"\"/secret:\"'"${RPC_SECRET_BASE64}"'\"/g' /usr/local/www/aria2/js/aria-ng*.js
 
-if [ "$ARIA2_SSL" = "true" ]; then
+if [[ "${ARIA2_SSL}" = "true" ]]; then
   echo "[INFO] Start aria2 with secure config and rpc-secret"
 
   /usr/bin/aria2c --conf-path="/app/conf/aria2.conf" \
@@ -13,15 +13,13 @@ if [ "$ARIA2_SSL" = "true" ]; then
     --rpc-private-key=/app/conf/key/aria2.key \
     --rpc-secret="${RPC_SECRET}" --rpc-secure
 
-elif [ "$ARIA2_SSL" = "false" && ${RPC_SECRET} != "" ]; then
+elif [[ "${ARIA2_SSL}" = "false" ]] && [[ "${RPC_SECRET}" != "" ]]; then
   echo "[INFO] Start aria2 with rpc-secret"
   /usr/bin/aria2c --conf-path="/app/conf/aria2.conf" \
     --enable-rpc \
     --rpc-listen-all \
     --rpc-secret="${RPC_SECRET}"
-
 else
-
   echo "[INFO] Start aria2 with standard mode"
   /usr/bin/aria2c --conf-path="/app/conf/aria2.conf" --enable-rpc --rpc-listen-all