remove logging when trying forceGC but no global.gc available

remove debug logging of etag cache

src/core/forceGC.js

@@ -1,19 +1,9 @@
-/**
- */
-
-import logger from './logger';
-
-
 /**
  * https://blog.jayway.com/2015/04/13/600k-concurrent-websocket-connections-on-aws-using-node-js/
  */
 function forceGC() {
   if (global.gc) {
     global.gc();
-  } else {
-    logger.warn('Garbage collection unavailable. '
-      + 'Pass --expose-gc when launching node to enable forced garbage '
-      + 'collection.');
   }
 }
 

src/routes/chunks.js

@@ -19,7 +19,6 @@ const chunkEtags = new Map();
 RedisCanvas.setChunkChangeCallback((canvasId, cell) => {
   const [x, y] = cell;
   const ret = chunkEtags.delete(`${canvasId}:${x}:${y}`);
-  logger.info(`etag delete ${ret}`);
 });
 
 /*
@@ -47,7 +46,6 @@ export default async (req: Request, res: Response, next) => {
     const preEtag = req.headers['if-none-match'];
 
     if (curEtag && preEtag === curEtag) {
-      logger.info(`etag ${curEtag} still the same`);
       res.status(304).end();
       return;
     }