refresh sdk manual and development manul

1. add barrier/bitmap/stopwatch/rwlock API to sdk manual
2. add barrier develop sample to develop manual

doc/code/2.3.6 barrier/main.c

@@ -0,0 +1,58 @@
+#include "tos_k.h"
+#include "mcu_init.h"
+
+#define STK_SIZE_TASK_WIZARD    512
+#define STK_SIZE_TASK_WARRIOR   512
+
+k_stack_t stack_task_warrior_0[STK_SIZE_TASK_WARRIOR];
+k_stack_t stack_task_warrior_1[STK_SIZE_TASK_WARRIOR];
+k_stack_t stack_task_warrior_2[STK_SIZE_TASK_WARRIOR];
+
+k_task_t task_warrior_0;
+k_task_t task_warrior_1;
+k_task_t task_warrior_2;
+
+k_barrier_t barrier;
+
+void entry_task_warrior_0(void *arg)
+{
+    printf("warrior 0: I'm searching the fragment\n");
+    tos_task_delay(1000);
+    printf("warrior 0: I have done my job, waitting other buddies done their job\n");
+    tos_barrier_pend(&barrier);
+    printf("warrior 0: all buddies find their fragment, do my next job\n");
+}
+
+void entry_task_warrior_1(void *arg)
+{
+    printf("warrior 1: I'm searching the fragment\n");
+    tos_task_delay(1500);
+    printf("warrior 1: I have done my job, waitting other buddies done their job\n");
+    tos_barrier_pend(&barrier);
+    printf("warrior 1: all buddies find their fragment, do my next job\n");
+}
+
+void entry_task_warrior_2(void *arg)
+{
+    printf("warrior 2: I'm searching the fragment\n");
+    tos_task_delay(2000);
+    printf("warrior 2: I have done my job, waitting other buddies done their job\n");
+    tos_barrier_pend(&barrier);
+    printf("warrior 2: all buddies find their fragment, do my next job\n");
+}
+
+int main(void)
+{
+    board_init();
+    tos_knl_init();
+    tos_barrier_create(&barrier, 3);
+
+    (void)tos_task_create(&task_warrior_0, "warrior_0", entry_task_warrior_0, NULL,
+                                4, stack_task_warrior_0, STK_SIZE_TASK_WIZARD, 0);
+    (void)tos_task_create(&task_warrior_1, "warrior_1", entry_task_warrior_1, NULL,
+                                4, stack_task_warrior_1, STK_SIZE_TASK_WIZARD, 0);
+    (void)tos_task_create(&task_warrior_2, "warrior_2", entry_task_warrior_2, NULL,
+                                4, stack_task_warrior_2, STK_SIZE_TASK_WIZARD, 0);
+    tos_knl_start();
+}
+