Tidy up gitignore
Tidy up gitignore

mysociety/popit,Sinar/popit,openstate/popit,mysociety/popit,Sinar/popit,openstate/popit,mysociety/popit,openstate/popit,mysociety/popit,openstate/popit,mysociety/popit,Sinar/popit,maxogden/popit,Sinar/popit,maxogden/popit