Added image filters to concert gallery
Set zoom-in cursor for galleries on larger screens
Added border to concert gallery items on hover
Fixed text colour on hover of external-link icon
Updated roadmap
Tweaked document download icon display
Corrected spelling from British to US English

programme => program
Fixed misspelt variable
Added conditional class for archive documents
Cleared concert gallery block
Added top margin to external links when no docs
Regenerated style.css