Promoting the enhanced branch

As any of you who watch pgsql-committers will have seen, I have now
moved the enahnced branch to CVS tip. Specifically, I have:

1) Created a REL-08_01_STABLE branch from CVS tip
2) Moved the REL-07_03_ENHANCED code to CVS tip
3) Bumped the version number to 08.02.0001
4) Standardised filenames and directory names (but not library names) to
reflect that we now only have an ODBC 3.51, Unicode build.
5) Defaulted the ODBC version number to 0x351 in all places (previously
it had different values in different files)
6) updated the Windows installer as appropriate, and introduced a new
version specific element to the path to allow concurrent installation
with 08.01.xxxx.
7) Updated all libnames to psqlodbc35w.(so|lib|dylib|whatever).
8) Updated the release notes.

The code builds as expected on Linux (with unixODBC) and Windows XP with
VC++ 6.0.

Please take a few minutes to checkout the code and ensure everything
looks as it should if you are able.

Thanks, Dave.