Bump the dates and Tor versions on the sample torrcs

src/config/torrc.minimal.in-staging

 ## Configuration file for a typical Tor user
-## Last updated 22 September 2015 for Tor 0.2.7.3-alpha.
+## Last updated 22 December 2017 for Tor 0.3.2.8-rc.
 ## (may or may not work for much older or much newer versions of Tor.)
 ##
 ## Lines that begin with "## " try to explain what's going on. Lines

src/config/torrc.sample.in

 ## Configuration file for a typical Tor user
-## Last updated 22 September 2015 for Tor 0.2.7.3-alpha.
+## Last updated 22 December 2017 for Tor 0.3.2.8-rc.
 ## (may or may not work for much older or much newer versions of Tor.)
 ##
 ## Lines that begin with "## " try to explain what's going on. Lines