Add semi-colon before and after packed js

This prevents JavaScript error if packed files do not start or hand with an expression delimiter.
Add semi-colon before and after packed js

This prevent JavaScript error if files do not start and end with a delimiter. This doesn't apply to inline script.
Trim leading semi-colons to prevent doubles
Merge pull request #1871 from shaffe-fr/1.6

[*] CORE : Add semi-colon before and after packed js files