Merge remote-tracking branch 'rich/platform' into development

* rich/platform:
  Remove dependency on sscanf in lib x509
  Fix extra guard in memory_buffer_alloc
  rebase from development
  implemented macro overriding for polarssl_* library functions
  fix bug introduced by the addition of snprintf and assert macro which caused tests to fail without polarssl_platform_c defined
  add initial symbols to config and checks to check_config to allow use of macros to define standard functions
  reformat and arrange additions to config alphabetically
  add missing checks to check_config
  add macro definition of assert using polarssl_exit
  modify library/memory_buffer_alloc.c, benchmark.c and the tests main code to use polarssl_exit
  add POLARSSL_PLATFORM_EXIT_ALT
  modify scripts/* and tests/* to use polarssl_snprintf
  modify programs/*.c to use polarssl_snprintf
  modify library/debug.c to use polarssl_snprintf
  modify library/x509*.c to use polarssl_snprintf
  modify library/net.c to use polarssl_snprintf
  modify oid.c to use polarssl_snprintf
  add platform_set_snprintf

Conflicts:
	library/memory_buffer_alloc.c
	programs/pkey/pk_sign.c
	programs/pkey/pk_verify.c
	programs/pkey/rsa_sign_pss.c
	programs/pkey/rsa_verify_pss.c
	programs/ssl/ssl_client2.c
	programs/ssl/ssl_pthread_server.c
	programs/test/benchmark.c
	programs/test/ssl_cert_test.c
diff --git a/programs/ssl/ssl_pthread_server.c b/programs/ssl/ssl_pthread_server.c
index 091d07a..524413c 100644
--- a/programs/ssl/ssl_pthread_server.c
+++ b/programs/ssl/ssl_pthread_server.c
@@ -33,6 +33,7 @@
 #include <stdio.h>
 #define polarssl_fprintf    fprintf
 #define polarssl_printf     printf
+#define polarssl_snprintf   snprintf
 #endif
 
 #if defined(_WIN32)
@@ -141,7 +142,7 @@
     memset( &ssl, 0, sizeof( ssl_context ) );
     memset( &ctr_drbg, 0, sizeof( ctr_drbg_context ) );
 
-    snprintf( pers, sizeof(pers), "SSL Pthread Thread %d", thread_id );
+    polarssl_snprintf( pers, sizeof(pers), "SSL Pthread Thread %d", thread_id );
     polarssl_printf( "  [ #%d ]  Client FD %d\n", thread_id, client_fd );
     polarssl_printf( "  [ #%d ]  Seeding the random number generator...\n", thread_id );