Follow symlinks

Solves #231 and updates the README to match.

README.md

@@ -19,7 +19,6 @@ watchpack high level API doesn't map directly to watchers. Instead a three level
 - The real watchers are created by the `DirectoryWatcher`.
 - Files are never watched directly. This should keep the watcher count low.
 - Watching can be started in the past. This way watching can start after file reading.
-- Symlinks are not followed, instead the symlink is watched.
 
 ## API
 

lib/DirectoryWatcher.js

@@ -392,7 +392,7 @@ class DirectoryWatcher extends EventEmitter {
 			const checkStats = () => {
 				if (this.closed) return;
 				this._activeEvents.set(filename, false);
-				fs.lstat(filePath, (err, stats) => {
+				fs.stat(filePath, (err, stats) => {
 					if (this.closed) return;
 					if (this._activeEvents.get(filename) === true) {
 						process.nextTick(checkStats);
@@ -625,7 +625,7 @@ class DirectoryWatcher extends EventEmitter {
 					}
 				});
 				for (const itemPath of itemPaths) {
-					fs.lstat(itemPath, (err2, stats) => {
+					fs.stat(itemPath, (err2, stats) => {
 						if (this.closed) return;
 						if (err2) {
 							if (