Bugs, Enhancements & golf

[xem]

Hi guys (@subzey @p01 @aemkei @bburky @rlauck)

I just released a first version of my tiny hex editor, and I need your help to enhance it and golf it :)

http://xem.github.io/hex/

Here are a few bugs I found:

• Save doesn't work on IE
• Display is broken when the textarea is empty
• Removing hex code by hitting backspace many times only works if the caret is at the end, not if it is in the middle of the textarea

And here are a few enhancements I imagined:

• Load via drag&drop
• Save with a better filename (random name on firefox by default) - is that even possible?
• Save with a file extension (if a file has been loaded, use its extension)
• Save with a better mime-type (octet-stream by default - is there a better default type?)
• Display more ASCII characters on the right panel (all printable chars instead of just 64-127, but we gotta escape <, >, &, etc.)
• Better interface

To join the enhancement & golfing, you can simply edit editor.min.html

Cheers, and HF!