v3.0.0

Major changes

• Add fallback_icon_color query parameter to API #14 (thanks @mmkal)
• Change User Agent for fewer grey icons #12 (thanks @mmkal)
• Support size range queries (80..100.120) #7
• Better support for cyrillic lettericons #10
• Introduce rewriting requests to just the domain part #9

Minor changes

• Use go 1.7.3
• Use Noto font
• Limit lettericon size to 256