Remove unused customer/profile.py

profile.py is not imported anywhere, and it's get_profile_class
is a duplicate of core/loading.py:get_profile_class.
Fix template error for product class.

templates/oscar/dashboard/catalogue/product_update.html tried to render
the product class via {{ product.product_class }}. 'product' is not
in the template context, but 'product_class' is, which gives the
expected result.
Add translation to Slovak language.
Removed stray </div> tag.
Merge pull request #502 from maikhoepfel/fix/producttemplate

Fix template error for product class.
Add slovakian locale to Makefile
Merge branch 'openhs-slovak-translation'

Conflicts:
	Makefile
Update all locale message files
Merge branch 'maikhoepfel-fix/profile_py'
Merge remote-tracking branch 'oscar/master'