Add '.mako' as an extension for mako templates

[rouge8]

https://www.makotemplates.org/

[asottile]

this was considered in the past, but I don't believe mako actually uses .mako as a file extension (their examples are all .txt and .html) -- some more official documentation of the mako extension would be needed to accept this

[rouge8]

Alembic (which is by the same author) uses .mako within its codebase :) https://github.com/sqlalchemy/alembic/tree/master/alembic/templates/generic

[asottile]

I use .mako too, but it's not documented at all

[rouge8]

Yeah, and it looks unlikely to be: sqlalchemy/mako#50

GH Linguist uses .mako (or .mao which I’ve never seen anywhere) to identify Mako files: https://github.com/github/linguist/blob/8083cb5a89cee2d99f5a988f165994d0243f0d1e/lib/linguist/languages.yml#L3166. It’s also one of the extensions used by default in pyramid_mako, but yeah, nothing official.