Validate data being used to create config class

[bmitch]

Here:

    /**
     * Config constructor.
     * @param array $rawData Raw config data.
     */
    public function __construct(array $rawData = [])
    {
        $this->filesToShow = $rawData['filesToShow'] ?? 10;
        $this->parallelJobs = $rawData['parallelJobs'] ?? 10;
        $this->commitsSince = $rawData['commitsSince'] ?? '10 years ago';
        $this->filesToIgnore = $rawData['filesToIgnore'] ?? [];
    }

[Lucky-Loek]

Will take a look at this today

[bmitch]

Fixed by #99