Config URL should run before loading profiles

[uilianries]

When base_profile_name is configured and it depends from a remote config folder, which should be solved by config_url, CPT will fail, because it tries to load that profile file first.

This PR fixes configuration/profile order, and introduces ConanApp (Conan >=1.18.0) correctly for profile cache when running Docker.

Changelog: Fix: Config URL should run before loading profiles

fixes #441

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  Signed-off-by: Uilian Ries [email protected]