error
Revert "added function pointer to free and compare data node, data search function node"

This reverts commit a04940221032fbcd20011708b1a88f85926589e4.
added function pointer to free and compare data node, data search function node
Fix bug add_after, add remove_first, remove_last functions, full example, destroy node(or not) on remove
Fix bug add_after, add remove_first, remove_last functions, full example, destroy node(or not) on remove
Fix bug add_after, add remove_first, remove_last functions, full example, destroy node(or not) on remove