Added support for different file encodings

The title says it all.

- Added iconv-lite
- New ini setting editor.encoding
- Failback to utf-8
- UI Header shows active encoding
I will call it fallbackEncoding and its needed!

The sequence i would prefer is:
1. Use the override encoding if it is set in the starting parameter **encoding**
2. If the parameter is not provided, try to autodetect the encoding using chardet
3. If 1. and 2. fails use fallbackEncoding from ini
4. If there is no fallbackEncoding provided in the ini return an error

What do you think about this sequence? Especially about 4. (The alternative to an error would be to just use utf-8)

P.S the chardet lib seems very cool, i couldnt found such a nice lib atm when i wrote the pullrequest. I am curious how it will perform :).