Log Message:
Update to Octave 2.2.0.

User-visible changes since previous release:
- Compatibility with Matlab graphics has been improved.
- New graphics functions.
- New experimental OpenGL/FLTK based plotting system.
- Functions providing direct access to gnuplot have been removed.
- The Control, Finance and Quaternion functions have been removed.
- Specific sparse matrix functions removed.
- Improvements to the debugger.
- Improved traceback error messages.
- Object Oriented Programming.
- Parsing of Command-style Functions.
- Block comments.
- Special treatment in the parser of expressions like "a' * b".
- Single Precision data type.
- Improved array indexing.
- Improved memory management.
- Improved performance for reduction operations.
- Sorting and searching.
- Range arithmetics.
- Various performance improvements.
- 64-bit integer arithmetic.
- Diagonal and permutation matrices.
- Improvements to fsolve.
- Improvements to the norm function.
- New functions for computing some eigenvalues or singular values.
- New QR and Cholesky factorization updating functions.
- New quadrature functions.
- New functions for reading and writing images.
- Other miscellaneous new functions.
- Changes to strcat.
- Improvements to the help functions.
- Deprecated functions.