Gravity Forms Signature Addon 4.6.1

Added a check to GFSignature::display_signature() to only use mime_content_type() if the signature image file is local.
- Added security enhancements.
- Added the gform_signature_delete_file_pre_delete_entry filter to disable deletion of the signature file or trigger deletion at a later time.

- Added a check to GFSignature::display_signature() to only use mime_content_type() if the signature image file is local.

- Fixed signature field not appearing on single page forms or multi-page forms embedded without AJAX.
- Fixed signature field disappearing on multi-page forms embedded via AJAX when rotating mobile device.
- Fixed extra lines added to signature when signing with Chrome on Android.
- Fixed issue where signature was clipped when rotating on mobile devices.