Remove the binding between current thread and module instance and bugs fix (#131)

Remove wasm_export_api.h that may confuse
Implement wasm_runtime_validate_app_str_addr()
Fix bugs of loader and pass more spec cases

Signed-off-by: Weining Lu <weining.x.lu@intel.com>

core/app-mgr/app-manager/module_wasm_lib.c

@@ -46,8 +46,9 @@ static bool wasm_lib_module_handle_host_url(void *queue_msg)
 }
 
 static module_data*
-wasm_lib_module_get_module_data(void)
+wasm_lib_module_get_module_data(void *inst)
 {
+    (void) inst;
     return NULL;
 }