Reads a user-specified configuration file,
located in a "config.yml" file in the working directory.
If this file is not found, reads a default package configuration file.
By default, the sits configuration file "config.yml" is located at
the directory "extdata" of the package.
The user can provide her additional configuration on an additional
configuration file, which is located by default on ~/.sits/config.yml.
To see the contents of the configuration file,
please use sits_config_show
.