add a npm script to clean static files collected by webpack

package.json

@@ -2,7 +2,8 @@
   "name": "genomics-workspace",
   "version": "1.0.0",
   "scripts": {
-    "build": "npm install && webpack && python2.7 setup.py"
+    "build": "npm install && webpack && python2.7 setup.py",
+    "clean": "node util/clean.js"
   },
   "private": true,
   "repository": {

util/clean.js

@@ -0,0 +1,50 @@
+const fs = require('fs');
+const path = require('path');
+
+const deleteFolderRecursive = function(path) {
+  if (fs.existsSync(path)) {
+    fs.readdirSync(path).forEach(function(file, index){
+      var curPath = path + "/" + file;
+      if (fs.lstatSync(curPath).isDirectory()) { // recurse
+        deleteFolderRecursive(curPath);
+      } else { // delete file
+        fs.unlinkSync(curPath);
+      }
+    });
+    fs.rmdirSync(path);
+  }
+};
+
+const projectRootPath = path.resolve(__dirname, '..');
+const gitIgnorePath = path.resolve(projectRootPath, '.gitignore');
+
+let files = fs.readFileSync(gitIgnorePath)
+              .toString()
+              .split('\n')
+              .filter(function(data){
+                if (
+                  data !== '' &&
+                  !data.startsWith('#') &&
+                  !data.startsWith('*') &&
+                  !data.startsWith('.')
+                ) {
+                    if (
+                      data.startsWith('/app/static') ||
+                      data.startsWith('/blast/static') ||
+                      data.startsWith('/clustal/static') ||
+                      data.startsWith('/hmmer/static')
+                    )
+                      return true;
+                }
+              });
+
+for (let f of files) {
+  f = path.resolve(projectRootPath, '.' + f);
+  if (fs.existsSync(f)) {
+    if (fs.lstatSync(f).isDirectory()) {
+      deleteFolderRecursive(f);
+    } else {
+      fs.unlinkSync(f);
+    }
+  } 
+}