Add redis mixin (oliver006#430)

* Add mixin for single redis instance

* Add mixin step to CI

* Add newlines

* Update READMEs

* update ci mixin step

* dont use pushd in ci step

* include mixin rules file

* Add deployment variable. Make instance variable multi-select and make each panel handle this

* Add UID to dashboard

* Move redis-mixin to contrib directory

* update README

* Update dashboard correctly

Bump github.com/sirupsen/logrus from 1.6.0 to 1.7.0 (oliver006#425)

Bumps [github.com/sirupsen/logrus](https://github.com/sirupsen/logrus) from 1.6.0 to 1.7.0.
- [Release notes](https://github.com/sirupsen/logrus/releases)
- [Changelog](https://github.com/sirupsen/logrus/blob/master/CHANGELOG.md)
- [Commits](sirupsen/logrus@v1.6.0...v1.7.0)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Issue oliver006#405 | Add sentinel info metrics (oliver006#418)

Use Golang 1.15, create a working test env via docker-compose (oliver…

…006#415)

* Golang 1.15, working test env via docker-compose, move bash scripts into Makefile

* Update readme

Add maxmemory_policy and memory reservation metrics (oliver006#409)

* add metric maxmemory_policy

* add memory reservation metrics

* add maxmemory_policy to unit test

Add TLS support for listening (oliver006#399)

Co-authored-by: Christian Schaefer <christian.schaefer@microfocus.com>

Pass RootCAs to dialTLSConfig (oliver006#393)

* Pass RootCAs to dialTLSConfig
Add Environment paramater REDIS_EXPORTER_TLS_CA_CERT_FILE
Add explanation for parameter REDIS_EXPORTER_TLS_CA_CERT_FILE to README

Add support for user auth introduced in Redis 6.0 (oliver006#392)

That also changes redigo/redis dependency to v1.8.2 which
is actually newer than 2.0.x tag and supports Redis ACL logins.

Co-authored-by: Mario Hros <git@reversity.org>

Fix slave_info missing label values (oliver006#383)

* Fix slave_info missing label values

* Add test about master_host and master_port

Fix arm builds, no parallel binary asset uploads to github (oliver006…

…#379)

* add  -parallel 1 to ghr binary upload, will take longer but maybe address validation errors

* GOARCH="arm" for arm builds