Release 3.9.0

18 new icons:

• filled/label
• outline/buildings
• outline/clock-bitcoin
• outline/cloud-bitcoin
• outline/eye-bitcoin
• outline/flag-bitcoin
• outline/heart-bitcoin
• outline/home-bitcoin
• outline/label-off
• outline/label
• outline/lock-bitcoin
• outline/mail-bitcoin
• outline/math-ctg
• outline/math-sec
• outline/math-tg
• outline/mood-bitcoin
• outline/photo-bitcoin
• outline/user-bitcoin