Default config and log paths used in config.r

[Ext3h]

By default, the R scripts will all attempt to write their log files to a relative location.

They will also attempt to read the configuration from a relative path.

This fails if codeface is installed to a path where the R scripts have no write permissions. E.g. when codeface was installed using "setup.py install".

[wolfgangmauerer]

Good catch -- we should make it mandatory to specify log paths (absolute or relative to the installation directory) in the configuration file. Additionally, it should be mandatory to specify a configuration file and disallow to use one implicitly.