[Nepomuk] A very old performance problem while deleting files.

[Weng Xuetian]

Hi,
Yes, I totally understand what nepomuk does... But It never stop interrupt 
user thread.... 

Anyway, there is a very old problem (from my memory.. when I really start use 
nepomuk, I currently using 4.7 beta 1), which is not so critical but annoying. 
When the nepomuk has hundreds of resource to be remove, like deleting a 
directory with many files, or deleting thousands of mails from kmail, it always 
takes a very long time to finish this process.

I think it's very easy reproduciable, just simply let nepomuk index a source 
code folder. When the index is done, delete the folder.