Update AdminSpecificPriceRuleController.php

Lors du ré affichage de la page de prix spécifique, le prix est coupé à 2 chiffres après la virgule, si notre ancien prix a plus de 2 chiffres il est tronqué et le prix change
[*] BO : Option to force new products to use (if enabled) Advanced Stock Managment/Depends On Stock
[-] Installer : fixtures : no gender for John
[-] Installer : fixture : order_message french
[-] Installer : fixtures : ordermessage french
[-] Installer : fixtures : profile > french
[-] Installer : fixtures : change alias / with new product
[-] fixed deprecated jQuery.live
[-] MO : mailalerts : new order translation works!
[-] Installer : fixtures : ref demo_1 to demo_7
[-] MO : blockcmsinfo : var uppercase
[-] Installer : configuration : var uppercase
[-] FO : Remove unnecessary translatable strings
Advanced stock and pack product - no warehouse

Refer to http://forge.prestashop.com/browse/PSCFV-11658
[*] BO : New employees only get notifications from orders/customer_messages/customer created after registration
Tabs cache set to "null" when using "add" function

$_getIdFromClassName is assigned "Null" to make it compatible with function "save". In P.S. 1.6.0.3 $_getIdFromClassName was assigned null after using "save function", but if a module is using "add" function new value is added to the array, but not reloaded. 

When a tab is created via "save" function $_getIdFromClassName is assigned "null", but if a module creates a tab using "add" function, newly adde tab is assign to $_getIdFromClassName (without reloading data from database), this causes $_getIdFromClassName to contain 1 value, and this prevents function "getIdFromClassName" to reload tabs data from database, and causes "getIdFromClassName" to return "false" in future calls.
 // typo availaible => available
// small change
 // Invalid return types in PHPDoc's
 // Redundant closing tags removed