Complete revamp of PCBuild8 directory.  Use subdirectories for each project under the main pcbuild solution.  Now make extensive use of property sheets to simplify project configuration. x64 build fully supported, and the process for building PGO version (Profiler Guided Optimization) simplified. All projects are now present, except _ssl, which needs to be reimplemented.  Also, some of the projects that require external libraries need extra work to fully compile on x64.

try to generate SVNVERSION information if subwcrev.exe
can be found.

Locals `revision` and `branch` were const-incorrect.

Also, stop determining Unicode sizes with PyString_GET_SIZE.

use of $(srcdir) in Makefile.pre.in so builds outside the source dir still
work.

Subversion revision number.

First, in an svn export, there will be no .svn directory, so use an in-file
$Revision$ keyword string with the keyword chrome stripped off.

Also, use $(srcdir) in the Makefile.pre.in to handle the case where Python is
build outside the source tree.

Add C API function Py_GetBuildNumber(), add it to the interactive prompt
banner (i.e. Py_GetBuildInfo()), and add it as the sys.build_number
attribute.  The build number is a string instead of an int because it may
contain a trailing 'M' if there are local modifications.

and a couple of functions that were missed in the previous batches. Not
terribly tested, but very carefully scrutinized, three times.

All these were found by the little findkrc.py that I posted to python-dev,
which means there might be more lurking. Cases such as this:

long
func(a, b)
	long a;
	long b; /* flagword */
{

and other cases where the last ; in the argument list isn't followed by a
newline and an opening curly bracket. Regexps to catch all are welcome, of
course ;)