Add confirmation component

- New ConfirmationInput component
- Add missing native resource config for templates.
- Add sample "component confirmation", use flag --no
  to switch default from yes to no.
- Fixes #366

spring-shell-core/src/main/resources/META-INF/native-image/resource-config.json

@@ -0,0 +1,9 @@
+{
+  "resources": {
+    "includes": [
+      {
+        "pattern": "org/springframework/shell/component/.*.stg"
+      }
+    ]
+  }
+}

spring-shell-core/src/main/resources/org/springframework/shell/component/confirmation-input-default.stg

@@ -0,0 +1,40 @@
+// message
+message(model) ::= <%
+<if(model.message && model.hasMessageLevelError)>
+<(">>>"); format="level-error"> <model.message; format="level-error">
+<elseif(model.message && model.hasMessageLevelWarn)>
+<(">>"); format="level-warn"> <model.message; format="level-warn">
+<elseif(model.message && model.hasMessageLevelInfo)>
+<(">"); format="level-info"> <model.message; format="level-info">
+<endif>
+%>
+
+// info section after '? xxx'
+info(model) ::= <%
+<if(model.defaultValue)>
+  <("(Y/n)"); format="item-disabled">
+<else>
+  <("(y/N)"); format="item-disabled">
+<endif>
+%>
+
+// start '? xxx' shows both running and result
+question_name(model) ::= <<
+<("?"); format="list-value"> <model.name; format="title">
+>>
+
+// component result
+result(model) ::= <<
+<question_name(model)> <model.resultValue; format="value">
+>>
+
+// component is running
+running(model) ::= <<
+<question_name(model)> <info(model)>
+<message(model)>
+>>
+
+// main
+main(model) ::= <<
+<if(model.resultValue)><result(model)><else><running(model)><endif>
+>>