Add done() calls to post handler so connection is returned to pool. Trying to fix 504 timeout errors from nginx. Initial testing looks good.

server.js

@@ -91,6 +91,7 @@ app.post('/', function(req, res){
                 "INSERT INTO alerts (origjson, coreid, published_at, status) VALUES ($1, $2, $3, $4);",
                 [JSON.stringify(req.body, null, 4), coreid, pubAt, status]
             );
+            done();
         });
     } else { // parse for minimal data from cell modem.
         var deviceid = JSON.stringify(req.body.data, null, 4).slice(1,4);
@@ -112,6 +113,7 @@ app.post('/', function(req, res){
                 "INSERT INTO alerts (origjson, coreid, published_at, status) VALUES ($1, $2, $3, $4);",
                 [JSON.stringify(req.body, null, 4), deviceid, received_at, statusFromCode]
             );
+            done();
         });
     }
     res.status(204).send('POST received');