util: use C++11 <random> instead of Boost.Random

Change-Id: Id0100a5ef14236f7e1d1f181af233e44bde3c1a2
Refs: #3599
diff --git a/src/util/random.hpp b/src/util/random.hpp
index e47b5fb..68dbe86 100644
--- a/src/util/random.hpp
+++ b/src/util/random.hpp
@@ -52,11 +52,9 @@
 generateSecureBytes(uint8_t* bytes, size_t size);
 
 /**
- * @brief Generate a cryptographically non-secure random integer from the range [0, 2^32)
+ * @brief Generate a non-cryptographically-secure random integer in the range [0, 2^32)
  *
- * This method uses Boost.Random routines
- *
- * This version is faster than generateSecureWord32, but it should not be used when
+ * This version is faster than generateSecureWord32, but it must not be used when
  * cryptographically secure random integers are needed (e.g., when creating signing or
  * encryption keys)
  */
@@ -64,11 +62,9 @@
 generateWord32();
 
 /**
- * @brief Generate a cryptographically non-secure random integer from range [0, 2^64)
+ * @brief Generate a non-cryptographically-secure random integer in the range [0, 2^64)
  *
- * This method uses Boost.Random routines
- *
- * This version is faster than generateSecureWord64, but it should not be used when
+ * This version is faster than generateSecureWord64, but it must not be used when
  * cryptographically secure random integers are needed (e.g., when creating signing or
  * encryption keys)
  */