Refactor capacitor plugins, clean up and organize android plugin classes

plugins/capacitor/AbsFileSystem.js

@@ -0,0 +1,13 @@
+import { registerPlugin, WebPlugin } from '@capacitor/core';
+
+class AbsFileSystemWeb extends WebPlugin {
+  constructor() {
+    super()
+  }
+}
+
+const AbsFileSystem = registerPlugin('AbsFileSystem', {
+  web: () => new AbsFileSystemWeb()
+})
+
+export { AbsFileSystem }