Duplicated Scripts after AJAX requests

Problem/Motivation

When ajax requests are made via jQuery.load scripts are duplicated which causes resets of static variables.

Steps to reproduce

Make an ajax request for a drupal page using jQuery.load

Proposed resolution

See if we already have the $L variable initialized before initializing again.
Use the global default of "AllowDuplicates:false"

Remaining tasks

none

User interface changes

none

API changes

none

Data model changes

none