* Handle different spellings of the PATH environment variable for Windows
* Ungristed elements of a target's requirements are now treated as
rules which transform the target's property set. The rules must have
the following signature:
transform-properties ( toolset variant : properties * )
and should return the new property set.
* Added target name adjustment feature for Python debugging targets.
tools/build/borland-tools.jam
tools/build/gcc-tools.jam
tools/build/intel-linux.jam
tools/build/metrowerks-tools.jam
tools/build/msvc-tools.jam
tools/build/mingw-tools.jam
* Adjustments to better support Python targets
tools/build/python.jam
* Lots of adjustments for building / testing Python targets:
PYTHON_LAUNCH variable prefixes Python executable name
-- can be used to invoke debugger.
PYTHON_ARGS variable postfixes Python executable name
CYGWIN_ROOT variable can be used to specify root of cygwin installation
[SVN r12071]
