refactor/polish ~ re-normalize whitespace

* minimize inconsistent/invisible whitespace

- consistent indentation (either spaces-only, tabs, *or* tabs with following spaces [for indentation])
- no internal/invisible tabs
- no trailing whitespace
- EOF EOLNs

src/uu/head/BENCHMARKING.md

@@ -20,7 +20,7 @@ and most other parts of the world.
 This particular file has about 170,000 lines, each of which is no longer
 than 96 characters:
 
-    $ wc -lL shakespeare.txt 
+    $ wc -lL shakespeare.txt
     170592      96 shakespeare.txt
 
 You could use files of different shapes and sizes to test the

src/uu/nl/Cargo.toml

@@ -29,4 +29,4 @@ name = "nl"
 path = "src/main.rs"
 
 [package.metadata.cargo-udeps.ignore]
-normal = ["uucore_procs"]
+normal = ["uucore_procs"]

src/uu/numfmt/Cargo.toml

@@ -24,4 +24,4 @@ name = "numfmt"
 path = "src/main.rs"
 
 [package.metadata.cargo-udeps.ignore]
-normal = ["uucore_procs"]
+normal = ["uucore_procs"]

src/uu/rm/src/rm.rs

@@ -217,7 +217,7 @@ pub fn uu_app() -> App<'static, 'static> {
         // This is solely for testing.
         // Do not document.
         // It is relatively difficult to ensure that there is a tty on stdin.
-        // Since rm acts differently depending on that, without this option, 
+        // Since rm acts differently depending on that, without this option,
         // it'd be harder to test the parts of rm that depend on that setting.
         .arg(
             Arg::with_name(PRESUME_INPUT_TTY)

src/uucore/src/lib/mods/backup_control.rs

@@ -56,7 +56,7 @@
 //!         .get_matches_from(vec![
 //!             "app", "--backup=t", "--suffix=bak~"
 //!         ]);
-//!    
+//!
 //!     let backup_mode = match backup_control::determine_backup_mode(&matches) {
 //!         Err(e) => {
 //!             show!(e);
@@ -321,7 +321,7 @@ pub fn determine_backup_suffix(matches: &ArgMatches) -> String {
 ///         .get_matches_from(vec![
 ///             "app", "-b", "--backup=n"
 ///         ]);
-///    
+///
 ///     let backup_mode = backup_control::determine_backup_mode(&matches);
 ///
 ///     assert!(backup_mode.is_err());