EXIF data is not retrieved using getimagesize

Problem/Motivation

When the toolkit is configured to use the PHP getimagesize() function to parse files in place of the default usage of the 'identify' binary, the EXIF image orientation is not fetched.

Proposed resolution

When using getimagesize() to parse the image file, fall back to read_exif_data() to fetch EXIF data, as soon as the orientation information is needed.

Remaining tasks

User interface changes

None.

API changes

None.

Data model changes

None.