Made Release.objects.current_version() more fail more silently.
Made Release.objects.current_version() more fail more silently.

This makes tests run better, and also breaks the dependancy of having to
have a current release for the site to run.

relekang/djangoproject.com,vxvinh1511/djangoproject.com,alawnchen/djangoproject.com,xavierdutreilh/djangoproject.com,nanuxbe/django,vxvinh1511/djangoproject.com,xavierdutreilh/djangoproject.com,hassanabidpk/djangoproject.com,khkaminska/djangoproject.com,gnarf/djangoproject.com,relekang/djangoproject.com,relekang/djangoproject.com,django/djangoproject.com,alawnchen/djangoproject.com,rmoorman/djangoproject.com,vxvinh1511/djangoproject.com,khkaminska/djangoproject.com,alawnchen/djangoproject.com,alawnchen/djangoproject.com,xavierdutreilh/djangoproject.com,rmoorman/djangoproject.com,gnarf/djangoproject.com,django/djangoproject.com,gnarf/djangoproject.com,nanuxbe/django,nanuxbe/django,rmoorman/djangoproject.com,django/djangoproject.com,django/djangoproject.com,django/djangoproject.com,khkaminska/djangoproject.com,hassanabidpk/djangoproject.com,django/djangoproject.com,nanuxbe/django,relekang/djangoproject.com,vxvinh1511/djangoproject.com,khkaminska/djangoproject.com,hassanabidpk/djangoproject.com,xavierdutreilh/djangoproject.com,gnarf/djangoproject.com,hassanabidpk/djangoproject.com,rmoorman/djangoproject.com