Resolve #65: Cast char to unsigned in isctype functions

Jan Breuer

2015-11-13 b5e8e4dc2bdeca39195a78d8d7f01bd7f099923c

 libscpi/test/test_fifo.c

@@ -76,7 +76,7 @@
    CU_ASSERT_TRUE(fifo_remove(&fifo, &value));
    CU_ASSERT_EQUAL(value, 5);
    TEST_FIFO_COUNT(0);
    

    CU_ASSERT_FALSE(fifo_remove(&fifo, &value));
    TEST_FIFO_COUNT(0);
}