removed casper theme; created exonum theme
removed casper theme; created exonum theme


Former-commit-id: 3495e0bb9c944615e9d4901126857e864e54e664
exonum/exonum,alekseysidorov/exonum,alekseysidorov/exonum,exonum/exonum,alekseysidorov/exonum,exonum/exonum,alekseysidorov/exonum,exonum/exonum