util: Redefine method for random number generation

The previous definitions random::generateWord* now generate
(cryptographically) "non-secure" random numbers from uniform
distribution using Boost.Random routines.  When (cryptographically)
secure random numbers are necessary, random::generateSecureWord*
routines should be used instead.

Change-Id: I52561119f7e558b4cfe0d250ca8a89e550d21b5f
Refs: #1760
diff --git a/wscript b/wscript
index 0f168b7..567d97d 100644
--- a/wscript
+++ b/wscript
@@ -68,7 +68,7 @@
         conf.define('HAVE_CXX11', 1)
 
     USED_BOOST_LIBS = ['system', 'filesystem', 'date_time', 'iostreams',
-                       'regex', 'program_options', 'chrono']
+                       'regex', 'program_options', 'chrono', 'random']
     if conf.env['WITH_TESTS']:
         USED_BOOST_LIBS += ['unit_test_framework']
         conf.define('HAVE_TESTS', 1)