Issues to address following initial release

[marcransome]

The following issues need addressing, as agreed, after the initial release of this service:

• Replace list of variables in README.md with Markdown table as per other repositories
• Remove manual terraform instructions from README.md
• Remove outdated references to stage variable in README.md
• Remove references to unused app_env_directory variable
• Rename arn variable used in cloud-watch module to provide additional context (e.g. lambda_arn)
• Replace hard-coded cron expression in aws_cloudwatch_event_rule resource with variable and rename any Terraform resources with time-specific names (e.g. payment_reconciler_daily and call_payment_reconciler_lambda_everyday) to decouple these from the variable cron expression
• Update s3_key in aws_lambda_function resource to use workspace_key_prefix (i.e. "${var.workspace_key_prefix}/${var.service}-${var.release_version}.zip")

Speak to @marcransome or @Jata2k for further details.