backend: don't support vcsserver.scm_app anymore

config: updated .ini files with cache settings

release: disable check phase for building installation

git: use smarter way for checking if repo is empty. This doesn't spam logs with some dulwich exceptions, we shouldn't really care about here.`

caches: enable cache TTL=30s for auth-plugins. - mostly due to this gives massive performance gains. - most of customers choose to use it. - svn gets *massive* boost from this.

docs: updated section about locale-archive problems

packages: normalize package emails.

auth-tokens: abstracted adding token for users into UserModel method for easier usage in scripts, and in future in API.

requests: added a default timeout for operation calling the endpoint url. Otherwise we can have a hanging calls for very long time.

docs: added info about --optimize flag for full text search.