callback of AbstractClass.include may be executed several times

/lib/include.js line 25: `AbstractClass.include = function (objects, include, cb) {`
If objects length is 0, and include is an array with multiple items, the cb will be executed several times.
While integrating with Express, this will cause the known issue "Can't set headers after they are sent."

To fix it, my suggestion is to add "return" before cb in line 53 as: `return cb(null, objects);`

The issue points to /lib/include.js line 25 and line 53. Start by examining the AbstractClass.include function to understand the loop logic. Check the condition when objects length is 0 and include is an array with multiple items. The fix suggested is to add a return statement before the callback. Test the change by running any existing tests related to include functionality or by creating a simple script to reproduce the callback being executed multiple times.

Scritto dal modello di indicizzazione a partire dal testo della issue.