#2587: Add executable file type to system.
#2587: Add update hooks to give fields to new type, and change existing files to new type.
#2587: Add executable file types to helper function.
Merge branch 'SCHOLAR-3.x' into 2587-new_file_type
#2587: Remove unneeded comment.
Merge pull request #2785 from openscholar/2587-new_file_type

New Executable File Type for odd files
Merge branch 'SCHOLAR-3.x' into 2734-show-parent-in-breadcrumb