[TASK] Working on filters + file upload, add alternative entry date field

Classes/Controller/JoblistController.php

Classes/Domain/Model/Job.php

Classes/Domain/Repository/CompanyRepository.php

Classes/Domain/Repository/JobRepository.php

Configuration/TCA/tx_sgjobs_domain_model_job.php

Resources/Private/Backend/Layouts/Default.html

Resources/Private/Language/de.locallang_db.xlf

Resources/Private/Language/locallang_db.xlf

Resources/Private/Partials/Filter.html

Resources/Private/Partials/Job.html

Resources/Private/Templates/Joblist/Index.html

Resources/Public/JavaScript/sgjobs.js

Resources/Public/Scripts/Backend.js

ext_tables.sql