Add compiled GTK3 theme source to .gitignore
Add compiled GTK3 theme source to .gitignore

sugarlabs/sugar-artwork,tchx84/debian-pkg-sugar-artwork,tchx84/debian-pkg-sugar-artwork,godiard/sugar-artwork,godiard/sugar-artwork,tchx84/debian-pkg-sugar-artwork,sugarlabs/sugar-artwork,i5o/sugar-artwork,godiard/sugar-artwork,sugarlabs/sugar-artwork,i5o/sugar-artwork,i5o/sugar-artwork