Enable WASI feature, enhance security and add SGX sample (#142)

Change emcc to clang
Refine interpreter to improve perforamnce

core/shared-lib/include/bh_common.h

@@ -8,7 +8,6 @@
 
 #include "bh_assert.h"
 #include "bh_platform.h"
-#include "bh_log.h"
 #include "bh_list.h"
 
 typedef void (*bh_print_function_t)(const char* message);

core/shared-lib/include/bh_memory.h

@@ -45,7 +45,7 @@ void bh_memory_destroy();
  * Get the pool size of memory, if memory is initialized with allocator,
  * return 1GB by default.
  */
-int bh_memory_pool_size();
+unsigned bh_memory_pool_size();
 
 #if BEIHAI_ENABLE_MEMORY_PROFILING == 0
 

core/shared-lib/include/bh_queue.h

@@ -54,7 +54,7 @@ void
 bh_queue_destroy(bh_queue *queue);
 
 char * bh_message_payload(bh_message_t message);
-int bh_message_payload_len(bh_message_t message);
+uint32 bh_message_payload_len(bh_message_t message);
 int bh_message_type(bh_message_t message);
 
 bh_message_t bh_new_msg(unsigned short tag, void *body, unsigned int len,