Optimize image copy in ShopImport module

2 things :
- copy images to new folder structure instead of legacy one since it's a PS 1.5 branch
- don't create all sizes of images at migration, there's an Admin controller for that (Admin > Settings > Images). That's speed up the import and remove duplicate code (less code to support).

+ some cleaning of unused variables
[-] IN : Remove warnings when safe_mode open_basedir missconfigured
[-] IN : Remove fails on upgrade coming to loop when upgrading again
[-] IN : Do not test module names if they are not directories
[-] IN : fix bad pathes
// remove Notice: Undefined index
// remove Warning on array_map()
[-] BO : ini_get('safe_mode') can return false
[-] IN : Do not duplicate images types when coming from 1.4, update it
[-] IN : remove warnings while upgrading
[-] Classes : Bug fix - FrontController, mobile & JS minifier fixed
[-] FO : fixed chinese search with multiple symbols #PSCFV-10322
[-] BO : Display the old image system migration tool if product images are in _PS_PROD_IMG_DIR_
[-] BO : FixBug PSCFV-10331 - Tax rules Pagination
[-] MO: Fix unifunc smarty errors if module is displayed on multiplehook without cache
// revert form https://github.com/PrestaShop/PrestaShop/commit/2874f1498352228c84df969c42e9d8f699a8afc5
Add some fields to Orders in Import module
Merge pull request #706 from sjousse/development

[*] MO : Add some fields to Orders in Import module
Merge pull request #699 from sjousse/patch-1

[*] MO : ShopImporter Optimize image copy in ShopImport module
fix imported prices