Merge branch 'release/v0.4.0' into develop
Development version.
Show every error only once.

Instead of showing the same error three times (e.g. in case of socket
timeout).
A slightly improved unknown error message.
Merge branch 'feature/improve-errors' into develop
Fixed the default log level to be "info".
New version.
Merge branch 'release/v0.4.1'