Remove modernizr rules for features on which we only soft depend

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

.modernizr.json

@@ -10,12 +10,9 @@
     "test/es5/specification",
     "test/css/objectfit",
     "test/storage/localstorage",
-    "test/workers/webworkers",
-    "test/indexeddb",
     "test/es6/array",
     "test/es6/collections",
     "test/es6/promises",
-    "test/serviceworker",
     "test/svg",
     "test/svg/asimg",
     "test/svg/filters",