remove Symbol monkey patch

[:one, :two].sort works in 1.9.3 and up, so we can remove this patch
Fix bi-weekly scheduling (+ all other varians)

In truth, just a typo fix.

https://bugzilla.redhat.com/show_bug.cgi?id=1139914
Merge pull request #742 from tenderlove/symbol_patch

remove Symbol monkey patch
remove unused miq_system_update.rb

The intent was to move most of the common
kickstart and rpm logic into this file.
Merge pull request #743 from mzazrivec/fix_weekly_scheduling

Fix bi-weekly scheduling (+ all other varians)
Merge pull request #744 from kbrock/prune_sysupdate

remove unreferenced library: miq_system_update.rb