piros/tor: Code added to Tor to support PIR-based onion service descriptor lookups @ acd6a4856bccff92eb241b18066ca7df577ab5f2

Nick Mathewson acd6a4856b Merge remote-tracking branch 'origin/maint-0.2.2'		%!s(int64=15) %!d(string=hai) anos
..
bug3118	e36f9d1d9b Link to libevent_openssl statically when requested	%!s(int64=15) %!d(string=hai) anos
dirvote_null_deref	1c668540fe Fix potential null pointer deref during dirvote	%!s(int64=15) %!d(string=hai) anos
mdesc_null_deref	1827e60976 Fix a potential null deref when rebuilding md cache	%!s(int64=15) %!d(string=hai) anos
microdesc_use	4cc348e896 Code to make clients fetch and use microdescriptors for circuit building	%!s(int64=15) %!d(string=hai) anos