[#gZVcpD77] Validate Customer Email Update

Branch: gZVcpD77-validate-customer-email-update
Issue: SparkartGroupInc/sparkart-services#305
Card: https://trello.com/c/gZVcpD77
Related: SparkartGroupInc/sparkart-tools#209, SparkartGroupInc/sparkart-core#102, https://github.com/SparkartGroupInc/sparkart-services/pull/329