Version 0.0.6 released.

- Improve ASCII and ISO-8859-1 detection.
- Improve language models: Greek, Hungarian.
- New supports:
  * Arabic - ISO-8859-6 and Windows-1256.
  * Danish - Windows-1252, ISO-8859-1 and ISO-8859-15.
  * Spanish - ISO-8859-1, ISO-8859-15 and Windows-1252.
  * Vietnamese - VISCII and Windows-1258.
- Improve single-byte encoding detection algorithm by giving more weight
  to "probable" sequences (less frequent than "positive" sequence, yet
  not "negative").
- `uchardet` command line tool improved:
  * exits with non-zero return values on error.
- CMake build improved with more options:
  * Binary can be installed to non-default dir.
  * Allow building static-only builds.
  * Allow not building the command line tool.
  * Add static lib destination.