reorganization of _examples and add some new examples such as iris+groupcache+mysql+docker

Former-commit-id: ed635ee95de7160cde11eaabc0c1dcb0e460a620

_examples/view/quicktemplate/templates/hello.qtpl

@@ -0,0 +1,14 @@
+Hello template, implements the Partial's methods.
+
+{% code
+type Hello struct {
+  Vars map[string]interface{}
+}
+%}
+
+{% func (h *Hello) Body() %}
+	<h1>{%v h.Vars["message"] %}</h1>
+	<div>
+		Hello <b>{%v h.Vars["name"] %}!</b>
+	</div>
+{% endfunc %}