Signature pad widget (8.x-1.3) - en to gu translation catalogue (4 entries)

en: Title
gu: શિર્ષક

en: Remove
gu: લોપ

en: Signature
gu: હસ્તાક્ષર

en: Background color
gu: પૃષ્ઠભૂમિ રંગ
