feat: No progress bars if stdout redirected

Progress bars pollute the output if it has been redirected to a file.

If stdout is redirected do not print progress bars

src/config.rs

@@ -3,6 +3,7 @@ use config_file::FromConfigFile;
 use serde::Deserialize;
 use std::path::Path;
 use std::path::PathBuf;
+use std::io::IsTerminal;
 
 use crate::display::UNITS;
 
@@ -31,7 +32,7 @@ impl Config {
         Some(true) == self.no_colors || options.is_present("no_colors")
     }
     pub fn get_disable_progress(&self, options: &ArgMatches) -> bool {
-        Some(true) == self.disable_progress || options.is_present("disable_progress")
+        Some(true) == self.disable_progress || options.is_present("disable_progress") || !std::io::stdout().is_terminal()
     }
     pub fn get_apparent_size(&self, options: &ArgMatches) -> bool {
         Some(true) == self.display_apparent_size || options.is_present("display_apparent_size")