Fixed versioning regexp
Fixed versioning regexp

booking list regexp was fixed in https://github.com/tomchristie/django-rest-framework/commit/8b97bb8f68970881190a3b62cf53495cc0e20786 but single booking wasn't for some reason, and `v1v2/bookings/123/` shouldn't be allowed here
cyberj/django-rest-framework,gregmuellegger/django-rest-framework,atombrella/django-rest-framework,callorico/django-rest-framework,gregmuellegger/django-rest-framework,pombredanne/django-rest-framework,davesque/django-rest-framework,agconti/django-rest-framework,pombredanne/django-rest-framework,uploadcare/django-rest-framework,sheppard/django-rest-framework,rhblind/django-rest-framework,linovia/django-rest-framework,ossanna16/django-rest-framework,sheppard/django-rest-framework,tomchristie/django-rest-framework,ossanna16/django-rest-framework,linovia/django-rest-framework,davesque/django-rest-framework,werthen/django-rest-framework,atombrella/django-rest-framework,sheppard/django-rest-framework,jpadilla/django-rest-framework,edx/django-rest-framework,johnraz/django-rest-framework,kgeorgy/django-rest-framework,pombredanne/django-rest-framework,abdulhaq-e/django-rest-framework,abdulhaq-e/django-rest-framework,agconti/django-rest-framework,callorico/django-rest-framework,werthen/django-rest-framework,uploadcare/django-rest-framework,gregmuellegger/django-rest-framework,werthen/django-rest-framework,rhblind/django-rest-framework,davesque/django-rest-framework,cyberj/django-rest-framework,tomchristie/django-rest-framework,dmwyatt/django-rest-framework,kgeorgy/django-rest-framework,dmwyatt/django-rest-framework,jpadilla/django-rest-framework,edx/django-rest-framework,uploadcare/django-rest-framework,abdulhaq-e/django-rest-framework,linovia/django-rest-framework,dmwyatt/django-rest-framework,ossanna16/django-rest-framework,jpadilla/django-rest-framework,edx/django-rest-framework,johnraz/django-rest-framework,callorico/django-rest-framework,atombrella/django-rest-framework,agconti/django-rest-framework,kgeorgy/django-rest-framework,johnraz/django-rest-framework,cyberj/django-rest-framework,rhblind/django-rest-framework,tomchristie/django-rest-framework