Introduce jquery formvalidator for com_languages

#### Executive summary

This PR converts the form validation on com_languages to use plain jquery (no mootools call on every form).
Also NO MORE INLINE SCRIPTS!

#### Testing

1. Apply first PR #4888 (!important)
2. Apply this PR
3. In the admin area go to com_languages and try to submit any form.

If no javascript errors are logged in your browser and the functionality remains the same your test is a pass in any other case please report the errors here

Please also check these:
administrator/index.php?option=com_checkin should demonstrate multiselect without mt
administrator/index.php?option=com_users&view=mail should demonstrate form sent and validate without mt
administrator/index.php?option=com_modules should demonstrate multiselect and combobox without mt
http://localhost/administrator/index.php?option=com_admin&view=sysinfo should demonstrate highlighter.js without mt
Logout and log in to demonstrate the use of noframes without mt.
oh oh :smiley: 
I have a doubt that writing function definition in jQuery ready() method can be a good practice, (in by link that you suggested I did not found something about it)
And I know only couple reasons when it can be not bad idea, but the current code do not related to any of these reasons :smile:
Also this part of the code use nothing from jQuery, and can work very good without it :wink:

And how it can block DOM? it do nothing with DOM, it just a definition.
If you do like you do, then JS parser parse  `jQuery.ready` and your code in it, and execute `jQuery.ready()` for add function definition to waiting the ready event. Then on `ready` event jQuery execute your function definition.
If you do as it was before, without jQuery, then JS parser parse your code and execute your function definition.

So, you still think that it will be better if all start make such thing? :smile: