Fix invisible file path text in PowerShell (#557)

change default path color on Windows

This avoids a conflict with a PowerShell configuration that causes text to be invisible.

Fixes #342

src/args.rs

@@ -692,7 +692,10 @@ impl<'a> ArgMatches<'a> {
     fn color_specs(&self) -> Result<ColorSpecs> {
         // Start with a default set of color specs.
         let mut specs = vec![
+            #[cfg(unix)]
             "path:fg:magenta".parse().unwrap(),
+            #[cfg(windows)]
+            "path:fg:cyan".parse().unwrap(),
             "line:fg:green".parse().unwrap(),
             "match:fg:red".parse().unwrap(),
             "match:style:bold".parse().unwrap(),