Reference dependency versions instead of duplicating them

doc/build-unix.md

@@ -42,15 +42,7 @@ Licenses of statically linked libraries:
  Boost         MIT-like license
  miniupnpc     New (3-clause) BSD license
 
-- Versions used in this release:
--  GCC           4.3.3
--  OpenSSL       1.0.1c
--  Berkeley DB   5.1.29.NC
--  Boost         1.55
--  miniupnpc     1.6
--  qt            4.8.3
--  protobuf      2.5.0
--  libqrencode   3.2.0
+- For the versions used in this release, see doc/release-process.md under *Fetch and build inputs*.
 
 System requirements
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