Create versions and changelogs for Snowflake pieces
This is a prerequisite for packaging Snowflake for Debian (legacy/trac#19409 (moved)).
We already have versions for the snowflake browser proxy. It could make sense to version different pieces of snowflake (client, browser proxy, proxy-go) separately since these pieces are largely distinct. That would be more work though. I'm ok with having one version/changelog for all the pieces and then just bumping the version number whenever it's convenient.