Minor bug: Float returned by listThreads

[bwollermann]

In line 208:
listThreads = args.maxthreads / 3

can return a float value which causes an error

For example:

INFO: Starting 66.66666666666666 delete threads...

Modify listThreads to force an integer value and it will work:
listThreads = int(args.maxthreads / 3)

[davem-git]

this helped me

[geekpete]

updated my PR to use listThreads = args.maxthreads // 3 which does the same with less brackets ;)