* update swagger to 0.20.1

* fiw swagger version for validate

* workaround broken swagger

only master brach is not working, latest release seems to work

Signed-off-by: Michael Gnehr <michael@gnehr.de>

* make vendor

Signed-off-by: Michael Gnehr <michael@gnehr.de>

* Don't export GO111MODULE

* set go-swagger to fixed release version

mentioned here: https://github.com/go-gitea/gitea/pull/7362#discussion_r300831537

Signed-off-by: Michael Gnehr <michael@gnehr.de>

* Add prometheus collector and route

* dep ensure -add github.com/prometheus/client_golang/prometheus

* dep ensure -update github.com/golang/protobuf

* add metrics to reserved usernames

* add comment head in metrics package

* fix style imports

* add metrics settings

* add bearer token check

* mapping metrics configs

* fix lint

* update config cheat sheet

* update conf sample, typo fix