favicon with a number

See #5, release log:

• 8be4aed by @yegor256: #5 trim
• 030dbdc by @yegor256: #5 js
• b7ad5a4 by @yegor256: #5 build clean
• b2ba158 by @yegor256: #5 TkFavicon

Released by Rultor 1.61.3, see build log