Update Snort binary to 2.9.4.6

Snort 2.9.4.6
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Update the Snort pfSense port to version 2.9.4.6 because the current 2.9.4.1 version goes EOL with rules updates on July 2, 2013.  This port update should be merged in concert with the Snort GUI package update 2.5.9 in the pfsense-packages repository.

This update includes the config directives "--enable-targetbased" and "--enable-perfprofile".  The target-based directive is required to support the new Host Attribute Table option being added to the 2.5.9 Snort GUI package.