Generate dynamic lists when entering the list rather than the category menu

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Enter the category menu
2.
3.

What is the expected output? What do you see instead?
Output is as expected but parsing multiple lists on 1000+ movie entries causes 
a delay. I would like it if the list is generated when entering it directly. 
For instance actors and directors lists take a long time to compile but maybe 
used infrequently. This way the delay would only occur on those occasions when 
the list is required rather than every time entering the plugin.

What version of Moving Pictures are you using? What version of MediaPortal? 1.3 
RC
What Skin? Titan


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Original issue reported on code.google.com by [email protected] on 12 Mar 2013 at 3:47