Fix Logic Bug in Rule Updates Triggered Under Unique Circumstances

CHANGE LOG
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DATE:  04/13/2013

Fix a logic bug in the rule update code that was resulting in a zero-length classification.config and reference.config file being written with certain combinations of rule set downloads selected.  The bug would only show when certain combinations of up-to-date and out-of-date rule sets existed for the selected rule downloads.  The resulting zero-length files then caused Snort to fail on the restart.

Also corrected a typo that was causing the unicode.map file to be named the gen-msg.map file.