what is update_against_templates in pootle 2.7?
Template updates now happen outside of Pootle.  The old update_against_template had performance problems and could get Pootle into a bad state.  To achieve the same functionality as update_against_templates do the following.  Assuming your project is myproject and you are updating language af:

sync_store --project=myproject --language=af
pot2po -t af template af
update_store --project=myproject --language=af

You can automate that in a script to iterate through all languages.  Use list_languages --project=myproject to get a list of all the active languages for that project.
I added a new template file from my project. Now I don't know how to make the languages update or get the new template file. I've read that 2.5 has update_against_templates but it's not in 2.7. How will update my languages?