v1.3 — Configurations and more

Thanks primarily to external contributors (@p @surmann @DavidFromNL) and to various people reporting issues (:heart:).

• Better behavior when --truncation is combined with --skip-empty-pages
• Allow specifying additional driver-specific options via --driver-options
• Allow disabling the default page size (--no-default-size), if the hardware does not support page size/location arguments
• Allow specifying a language for OCR (--language)
• Configurable white thresholds for empty page detection
• Software-based (ImagicMagick) post-processing to alter brightness and contrast (--brightness-contrast-sw)
• Allow passing an empty value for the device argument, which can help when using scanbd (see the README)
• Save script configuration in files to avoid having to specify the relevant arguments every time the script is used
• Fix various bugs