HTTrack Website Copier

Android 6 & 7 fixes (crashes at startup and/or during browse), SDcard is now selected by Additional Android 6 (Marshmallow) and 7 (Nougat) fixes related to crash at startup and/or issues accessing downloaded websites (crashes when asking to browse or see the documentation), and update to the latest HTTrack source codebase. Sorry for the Android 6/7 issues, related to drastic changes in policy from Android.as output.