Update and improve Persian (fa) translations

As there is [a plan](https://www.mediawiki.org/wiki/Outreach_Program_for_Women/Round_8#Switching_Semantic_Forms_autocompletion_to_Select2) to use this library on MediaWiki, [as a MediaWiki translator](https://translatewiki.net/wiki/User:Ebraminio) I felt I should improve its translations here before it would be used on Wikipedia. Some notes that I've applied on this commit and am I mentioning them for future reference:
* Space or any character should be placed on logical place so when it will used on a RTL it will be shown on its correct place, so " لطفا" that you see on LTR context visually right in fact is wrong and "لطفا " on deployment will be seen on its right place.
* Per [Orthography guide of Persian Academy](http://www.persianacademy.ir/fa/vijegidas.aspx), use of ًـ is not optional but needed.
* «بارگذاری» means "Upload" and «بارگیری» means "Load". It shouldn't be confused.
* «نویسه» is very common equivalent to character, e.g. [1](http://www.yjc.ir/fa/news/4570840/%D9%86%D9%88%DB%8C%D8%B3%D9%87-%D8%AE%D9%88%D8%A7%D9%86-%D9%86%D9%88%D8%B1%DB%8C), no need to use transliteration of "Character".