Function initialize 

pub fn initialize(config: &Config, dir: Option<&str>) -> Result<(), PathError>

Initialize the timelog directory supplied and create a .timelogrc config file. If no directory is supplied default to ~/timelog

Errors

• Return PathError::CantCreatePath if cannot create timelog directory
• Return PathError::FileAccess if we are unable to write the configuration.
• Return PathError::InvalidPath if the path is not valid

Panics

If the canonicalized path cannot be converted to a string.