Fix haxelib path fallback functionality on windows (#1241)

The check on line 134 would never work properly on windows, because the
line had a CR character so FileSystem.exists returned false. This meant
that if a library was resolved via a name that doesn't exactly match the
`-D` flag set by haxelib, e.g. Hxcpp instead of hxcpp or via an alias,
then it would be reported as missing.

Author: tobil4sk

tools/hxcpp/PathManager.hx

@@ -111,8 +111,8 @@ class PathManager
          catch (e:Dynamic) {}
 
          Log.verbose = cache;
-         
-         var lines = output.split("\n");
+
+         var lines = ~/\r?\n/g.split(output);
          var result = "";
          var re = new EReg("^-D " + haxelib + "(=.*)?$", ""); //matches "-D hxcpp=3.1.0" or "-D hxcpp", but not "-D hxcpp-extras"
          for (i in 1...lines.length)