archivebot.py: handle standard arguments

Added a call of pywikibot.handleArgs to handle arguments
such as -putthrottle:n.

Change-Id: I97b14b21f3c4c73183f85473926e0b204c4f1abd
(cherry picked from commit a7443e63f5b4759e921f6574e8f1b2c7437494d8)
Merge "archivebot.py: handle standard arguments"