Use consistent directory to store gocupi_config.xml

[brandonagr]

Currently it just checks in the current working directory, and not the directory that the gocupi executable is in, since gocupi is in path the settings file it reads depends on where your current directory is as to where it will create a settings file

Should also search the default gopath directory for data files when drawing, so users can start using the example files immediately no matter what their current directory is