Update jefreg.php

- fixed the regex to clean the commercial file. It was not cleaning the spaces properly. 
- fixed the regex that detects the commcerial file. Removed the colon in the expression. The expression is supposed to detect *[appid]=>[link], not *:[appid]=>[link]
Update jefreg.php

You must set the field as required. If the field is not required when $jefreg['installat'] is empty, the rule test for the field will return as true (i.e. valid).
Rename en-GB.en-GB.plg_system_jefreg.ini to en-GB.plg_system_jefreg.ini

Removed the extra "en-GB.". It only needs one. So, the file should be "en-GB.plg_system_jefreg.ini", not "en-GB.en-GB.plg_system_jefreg.ini"
Merge pull request #1 from mgilkes/patch-1

Patch 1