Add support for AIFF

- add support for
  - TagLib::RIFF::File abstract class
  - TagLib::RIFF::AIFF::File class
  - TagLib::RIFF::AIFF::Properties class

- added swig code for RIFF and AIFF.
- added test code for reading/writing tags (ID3v2)
    to/from AIFF files, including cover-arts.
- added an AIFF-encoded audio file for tests.
- added documentation.
generate swig wrappers for TagLib 1.7
remove tests for TagLib 1.8+ features
remove unnecessary RIFF::File class
add test code for examples shown in the documentation

this is to ensure that examples actually work
(first run test code, then copy/paste to documentation)
add test code for examples shown in the documentation (oops)

this is to ensure that examples actually work
(first run test code, then copy/paste to documentation)

(commit missing file test/aiff_examples_test.rb)
regenerate AIFF wrapper using swig 2.0.11 (#54)
fix spelling typo
Merge pull request #52 from tchev/aiff

Add support for AIFF