Windows: ":" is an illegal char for a file name. Fixes #4026

Author: Federico Fissore

arduino-core/src/cc/arduino/Compiler.java

@@ -355,6 +355,7 @@ private void saveHex(String compiledSketch, String copyOfCompiledSketch, Prefere
     try {
       compiledSketch = StringReplacer.replaceFromMapping(compiledSketch, prefs);
       copyOfCompiledSketch = StringReplacer.replaceFromMapping(copyOfCompiledSketch, prefs);
+      copyOfCompiledSketch = copyOfCompiledSketch.replaceAll(":", "_");
 
       Path compiledSketchPath;
       Path compiledSketchPathInSubfolder = Paths.get(prefs.get("build.path"), "sketch", compiledSketch);