AssetInput: don't show as invalid when there is no input
AssetInput: don't show as invalid when there is no input

BitSharesEurope/wallet.bitshares.eu,BitSharesEurope/graphene-ui-testnet,bitshares/bitshares-ui,BitSharesEurope/graphene-ui-testnet,BitSharesEurope/graphene-ui-testnet,BitSharesEurope/testnet.bitshares.eu,bitshares/bitshares-2-ui,BitSharesEurope/testnet.bitshares.eu,bitshares/bitshares-ui,BitSharesEurope/wallet.bitshares.eu,bitshares/bitshares-ui,BitSharesEurope/wallet.bitshares.eu,BitSharesEurope/wallet.bitshares.eu,BitSharesEurope/testnet.bitshares.eu,bitshares/bitshares-2-ui,BitSharesEurope/graphene-ui-testnet,bitshares/bitshares-ui,BitSharesEurope/testnet.bitshares.eu,bitshares/bitshares-2-ui