added support for hot-key function

增加支持热键功能。热键定义范围：字母A-Z，数字0-9

1、alt+热键，定位到输入字段，字段包括text-line、drop-down、date-time、check、radio、textarea 2、ctrl+热键，点击按钮，包括container-dialog、dynamic-dialog、button-menu、link 3、在同一个form里面按回车键，会循环找输入框焦点 4、如果多个输入字段的热键一样，按alt+热键会在这些字段中循环

现在发现：ctrl+n、ctrl+w是浏览器缺省热键，无法使用

方案的基本是思路是通过自定义的moqui-key，在界面渲染的时候，绑定到对应的控件上，然后监控全局的键盘事件，进行相应的处理。不影响控件自己的按键处理逻辑。

如何使用： a、输入字段在中增加moqui-key属性 b、按钮字段在自己的属性增加moqui-key属性， c、基本是title或button-text在哪里定义，moqui-key就在哪里定义 d、无论大小写，系统自动转化为大写

特别定义： ctrl+· （Backquote），qapps下，open/close 左边主菜单；vapps/apps下，返回主菜单界面

关于screen和form 的xsd文件修改，需要在framework库中提交，如果本PR审核通过，再提交PR

Added support for hotkey function. Hotkeys define scope: letters A-Z, numbers 0-9

alt+ hotkey, focus to the input field, includes text-line、drop-down、date-time、check、radio、textarea
ctrl+ hotkey, click button, includes container-dialog、dynamic-dialog、button-menu、link
Pressing the Enter key in the same form will cycle through the focus of the input field.
If multiple input fields have the same hotkey, pressing alt+hotkey will cycle through those fields

Now I found that Ctrl+N, Ctrl+W are the default hotkeys of the browser and cannot be used

The basic idea of the solution is to bind to the corresponding control when the interface is rendered through a custom moqui-key, and then monitor the global keyboard events for corresponding processing. It does not affect the control's own keyboard processing logic.

How to use: a. For input fields, add the moqui-key attribute to the b. For buttons, add the moqui-key attribute to itself c. Basically, where the title or button-text is defined, moqui-key is defined d. Regardless of the case, the system automatically converts to uppercase

Special Definitions: ctrl+· （Backquote），in qapps mode，open/close left main menu；in vapps/apps mode，return to main menu screen

For changes to the XSD files of screen and form, need to submit them in the moqui/Framework library.If this PR is approved, submit that PR again

moqui / moqui-runtime

added support for hot-key function #224