Add DragonFly BSD support (#176)

src/steps/os/dragonfly.rs

@@ -0,0 +1,29 @@
+use crate::error::{Error, ErrorKind};
+use crate::executor::RunType;
+use crate::terminal::print_separator;
+use crate::utils::require_option;
+use failure::ResultExt;
+use std::path::PathBuf;
+use std::process::Command;
+
+pub fn upgrade_packages(sudo: Option<&PathBuf>, run_type: RunType) -> Result<(), Error> {
+    let sudo = require_option(sudo)?;
+    print_separator("DrgaonFly BSD Packages");
+    run_type
+        .execute(sudo)
+        .args(&["/usr/local/sbin/pkg", "upgrade"])
+        .check_run()
+}
+
+pub fn audit_packages(sudo: &Option<PathBuf>) -> Result<(), Error> {
+    if let Some(sudo) = sudo {
+        println!();
+        Command::new(sudo)
+            .args(&["/usr/local/sbin/pkg", "audit", "-Fr"])
+            .spawn()
+            .context(ErrorKind::ProcessExecution)?
+            .wait()
+            .context(ErrorKind::ProcessExecution)?;
+    }
+    Ok(())
+}