Replace OpenSSL with PolarSSL

Works on windows, not yet cmake.

Externals/polarssl/doxygen/input/doc_rng.h

@@ -0,0 +1,25 @@
+/**
+ * @file
+ * Random number generator (RNG) module documentation file.
+ */
+
+/**
+ * @addtogroup rng_module Random number generator (RNG) module
+ * 
+ * The Random number generator (RNG) module provides random number
+ * generation, see \c ctr_dbrg_random() or \c havege_random().
+ *
+ * The former uses the block-cipher counter-mode based deterministic random
+ * bit generator (CTR_DBRG) as specified in NIST SP800-90. It needs an external
+ * source of entropy. For these purposes \c entropy_func() can be used. This is
+ * an implementation based on a simple entropy accumulator design.
+ *
+ * The latter random number generator uses the HAVEGE (HArdware Volatile
+ * Entropy Gathering and Expansion) software heuristic which is claimed 
+ * to be an unpredictable or empirically strong* random number generation.
+ *
+ * \* Meaning that there seems to be no practical algorithm that can guess
+ * the next bit with a probability larger than 1/2 in an output sequence.
+ *
+ * This module can be used to generate random numbers.
+ */