How to version control PostgreSQL schema with comments?

I version control most of my work with Git : code, documentation, system configuration. I am able to do that because all my valuable work is stored as text files. I have also been writing and dealing with lot of SQL schema for our Postgres database. The schema includes views, SQL functions, and we will be writing Postgres functions in R programing language (via PL/R ). I was trying to copy and past the chunks schema that I and my collaborators write but I forget to do that. The copy and past action is repetitive and error prone. The pg_dump / pg_restore method will not work because it looses comments. Ideally I would like to have some way to extract my current schema into a file or files and preserve the comments so that I can do version control. What is the best practice to version control schema with comments?