[split] language translations concatenation issues

[mvlcek]

Just a few comments regarding the Translate plugin and its advantages:

• it scans the plugin's or GetSimple core code to retrieve all necessary translations - great, if you are adding text placeholders but only want to assign texts later.
  
• if a text placeholder is found in the language file, but not in the source code, it's marked (grayed out), but can still be translated.
  
• it shows all (installed) languages and their completion percentages.
  
• you normally translate from one language to another language - you don't need to understand what e.g. PAGE_NOTEXIST means, but can translate "The requested page does not exist" to your language. You can even translate, if you don't know English (well enough), as long as there exists a language you know.
  
• you can filter the list to only show missing translations
  
• you can save and immediately view the result by navigating to the respective admin page.
  

Currently I have a version that can download/upload from/to Transifex.net (as long as there is a project getsimple_<pluginname> and you are authorized for it). I'm not sure if this is (easily) possible for Github, too.