Add new example file_info

Like stdin_info, only displays the data of a file, but does not extract
the contents.

examples/file_info.rs

@@ -0,0 +1,38 @@
+extern crate zip;
+
+use std::fs;
+
+fn main() {
+    std::process::exit(real_main());
+}
+
+fn real_main() -> i32 {
+    let args: Vec<_> = std::env::args().collect();
+    if args.len() < 2 {
+        println!("Usage: {} <filename>", args[0]);
+        return 1;
+    }
+    let fname = std::path::Path::new(&*args[1]);
+    let file = fs::File::open(&fname).unwrap();
+
+    let mut archive = zip::ZipArchive::new(file).unwrap();
+
+    for i in 0..archive.len() {
+        let file = archive.by_index(i).unwrap();
+        let outpath = file.sanitized_name();
+
+        {
+            let comment = file.comment();
+            if !comment.is_empty() {
+                println!("Entry {} comment: {}", i, comment);
+            }
+        }
+
+        if (&*file.name()).ends_with('/') {
+            println!("Entry {} is a directory with name \"{}\"", i, outpath.as_path().display());
+        } else {
+            println!("Entry {} is a file with name \"{}\" ({} bytes)", i, outpath.as_path().display(), file.size());
+        }
+    }
+    return 0;
+}