add README.md

Author: eecjimmy

README.md

@@ -0,0 +1,38 @@
+## usage
+
+- `composer require eecjimmy/basic`
+
+```php
+namespace demo;
+use eecjimmy\Basic\CacheableTrait;
+class Demo
+{
+
+    use CacheableTrait;
+
+    public function getUser()
+    {
+        return $this->cacheGet(__METHOD__, function () {
+            echo "cache missing...\n";
+            return 'user';
+        });
+    }
+
+    public static function getStudent()
+    {
+        return self::cacheGetStatic(__METHOD__, function () {
+            echo "cache missing...\n";
+            return 'student';
+        });
+    }
+
+    public function getWithArgument($a)
+    {
+        $key = md5(__METHOD__ . json_encode(func_get_args()));
+        return $this->cacheGet($key, function () {
+            echo "cache missing...\n";
+            return 'with-argument';
+        });
+    }
+}
+```