Fixed auto-debug, the 'dbglvl_matches' contained an empty string, which was true
Merge pull request #69 from matthiasbeyer/fix-autoenabled_debug_printing

Fixed auto-debug, the 'dbglvl_matches' contained an empty string, which was true
Moved metadata methods to TreeElement superclass
Added TreeElement#read_metadata! abstract supermethod + test
Specify the metadata file name only once
Override the #read_metadata! method here, but dont do fancy stuff
Pull this method up to the superclass, we need it elsewhere too
Change the implementation of #parse_metadata!

Change the implementation of #parse_metadata! to return the actual metadata
Added implementation of #read_metadata! for {Day, Month, Year} class
Pulled #read_metadata! up into TreeElement class

Added File-extists check, adapted tests
Outsourced metadata_file_path generation
We should use the metadata file path to read the metadata from
The metadata file path of an entry is the entries path itself
Ensure we do not remove everything endlessly here
Now we can ensure that the metadata is written in _one_ step
Dont't do unneccessary file system operations

Ensure that we do not do unneccessary file system operations by
re-writing the metadata every time when calling
the #ensure_metadata_written! method
Ensure we set the flag when we change metadata
Added helper method

Added helper method for getting all tree objects from the Tree class
Use the new #objects method to iterate
Try to add the metadata variable before modifying it