For user-generated repos, the default path/URL is .*/fdroid/repo, with
fdroid/ as the root where the 'fdroid' tool operates. This makes for a URL
that is quite unique and easily matched automatically using patterns, like
in fdroidclient.
For those who don't like the standard, they can override the errror from
config.py using nonstandardwebroot = True
This is quite simple, but makes the user experience consistent when setting
up repos: run init then update locally, then run init then update on the
server.
This patch also includes PEP8 formatting fixes
