backup_control: Implement custom error type
Implements an error type based on `UError` that replaces the previously used
error strings. The errors are currently returned when determining the backup
mode, but extensions for future uses are already in place as comments.
@@ -16,6 +16,7 @@ edition = "2018"
path="src/lib/lib.rs"
[dependencies]
+clap = "2.33.3"
dns-lookup = { version="1.0.5", optional=true }
dunce = "1.0.0"
getopts = "<= 0.2.21"
