###Useful PHP tools for WordPress plugin development
Activator: activate plugin
ArrayUtil: useful methods for Array manipulation (find value by key, find value by index, get keys from multidimensional array)
Editor: include WP built-in rich text editor
FieldsFactory: create custom HTML fields fastly
Post: CRUD wrapper for WP_Post manipulation
Render: render template with variables
Response: parse WP_Ajax_Response results
Validator: validate data from form