Fix dockerfile alternate paths

Remove ./ relative path notation which doesn't work on latest version of Docker + Compose

See: https://docs.docker.com/compose/compose-file/#dockerfile

Minor enhancements for php Dockerfile

Fix PHP-CS-Fixer config

Update admin

Fixed docker for Windows

Revamp the docs

Fix assets:install command for Docker in composer.json

Use the cached mode for some Docker volumes

Use scanelf to detect runtime deps

Bump deps. Downgrade to Postgres 9.6.

Upgrade Flex

Enable autowiring strict mode and class loader inlining

[client] fixed the package name