Modify central view resolver to honour template settings

Currently central view resolver tries to determine the right template for a category using the following logic:
1. Attempt to see if category has at least one product and if it does the template is 'products'
2. See if category has a template - and use it if it does
3. If this category has sub categories - 'subcats'
4. Otherwise 'category'

A better solution would be to check for template first thus avoiding unnecessary FT query and also ensuring that the template setting is honoured.

Only if we do not have template set should we attempt to use above logic.