FileCollector: Convert directories to paths
Setting: Use only directory of origin

The origin member of the setting holds the originating _file_. Thus we
should strip of the file and take only the directory instead.
CliParser: Use correct origin

Since the CliParser specifies the origin as a directory and the Setting
uses a path to a file we need to append a directory seperator.
Setting: Return absolute path for path conversion
coalib: Use dirname instead of split

This is more efficient and straightforward.
processes: Add SectionExecutor
processes: Add SectionExecutorTest
SectionManagerTest add