Frontend Search does not work with terms containing special characters (ó, â)

[coretoco]

Is your feature request related to a problem?

The current search function in the frontend does not return a result if the product name contains a special character (like â or ó) This is not the case in the backend search (Store Administration)
Example: Productname: "Château Biac 2012 AC Côtes de Bordeaux"
Frontend: Search for "Côtes" returns nothing (search for "Cotes" returns nothing)
ShopAdmin: Search for "Côtes" returns product (search for "Cotes" returns nothing)

Describe the solution you'd like

The Frontend Search should return a product if the product name is correctly entered.

Describe alternatives you've considered

The search could be a bit more relaxed globally. See also #141