fix(deps): lock gulp-rev-all to 0.8.18

Author: balthazar

app/templates/package.json

@@ -26,7 +26,7 @@
     "gulp-plumber": "^1.0.0",<% if (filters.e2e) { %>
     "gulp-protractor": "^1.0.0",<% } %><% if (filters.reload === 'livereload') { %>
     "gulp-replace": "^0.5.2",<% } %>
-    "gulp-rev-all": "^0.8.13",
+    "gulp-rev-all": "0.8.18",
     "gulp-sass": "^1.3.2",
     "gulp-uglify": "^1.1.0",
     "gulp-usemin": "^0.3.11",