Redis storage support

Changes from #44:

• Added Redis storage support thanks to @sebastianmacarescu

Gzip support

Changes from #33:

• gzip support by default
• dropped support for TLS 1.0 and 1.1 since it's getting deprecated
• increased max file size to 100MB by default

Minor release - Introducing RESOLVER_ADDRESS variable

Changelog:

• #32 Added RESOLVER_ADDRESS env variable to make it possible to override default 8.8.8.8 value, as it's not always working

Stable release

Available as docker pull valian/docker-nginx-auto-ssl:1.0.0

From this point, I'm starting properly versioning images.

A list of all available tags can be found here. Builds are automated from this repository, so you can easily pinpoint your image version to one of tags or use latest that will automatically follow the master branch.

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Pull requests:

• Update lua-resty-auto-ssl version #31 (fixes #29)

Websocket support

• Added support for WebSockets #22