Top-level bootstrap/configure/make.

This huge changeset is to turn the various "sort-of" independent
subpackages of MonetDB into one coherent package.  The principle idea
is that we now have a single top-level configure and make instead of
having to run configure and make many times to build everything.

From now on, the way to build MonetDB is to run the command
"./bootstrap" in the top-level directory, and then to run
".../configure" and "make" in the build directory (which can be the
same as the source, but doesn't have to be).  On Windows, the way to
build is to run "nmake" in the NT subdirectory or to run "nmake /f
..\NT\Makefile" in an empty directory underneath the top level.

The subpackages affected are: MonetDB, clients, MonetDB4, MonetDB5,
sql, pathfinder, geom, testing, java.  The python subpackage is not
(yet?) affected: it still requires you to run setup.py.  Also not
affected is template (although it likely won't currently work) since
it is meant as a template for external (to the MonetDB suite)
extensions.

The top-level configure has a number of options to enable and disable
the building of subpackages:
  --enable-monetdb4       enable support for MonetDB4 (default=auto)
  --enable-monetdb5       enable support for MonetDB5 (default=auto)
  --enable-sql            enable support for MonetDB/SQL (default=auto)
  --enable-geom           enable support for geom module (default=auto)
  --enable-pathfinder     enable support for MonetDB/XQuery (default=auto)
  --enable-pftijah        enable support for TIJAH (default=auto)
  --enable-probxml        enable support for PROBXML (default=auto)
  --enable-odbc           compile the MonetDB ODBC driver (default=auto)
  --enable-testing        enable support for testing (default=auto)
  --enable-console        enables direct console on the server (involves
                          security risks)
  --enable-java           (try to) build Java components
  --enable-jdbc           build the MonetDB JDBC driver
  --enable-xrpcwrapper    build the MonetDB XRPC wrapper
  --enable-merocontrol    build the Merovingian control driver

The options to specify the presence and location of programs and
libraries that are used to build the subpackages were of course also
integrated into the top-level configure, as were the following
options:
  --with-default-backend=BACKEND
                          select a default back-end
                          (milprint_summer/algebra/sql) for Pathfinder
                          (default=algebra)
  --with-password-backend=HASHALG
                          password hash algorithm, one of MD5, SHA1,
                          RIPEMD160, SHA224, SHA256, SHA384, SHA512, defaults
                          to SHA512

Note that the Pathfinder configuration without MonetDB4 is still possible:
.../configure --disable-monetdb4 --disable-monetdb5 --enable-pathfinder ...

Other changes include the following:
- One top-level MonetDB.spec file so that all RPMs can be built in one
  go;
- One top-level debian subdirectory with Debian/Ubuntu configuration;
- Removed all *-config and *-config.bat files: there use is superseded
  by the single top-level configure and various *.pc (pkgconfig) files;
- All paths in Makefile.ag files to other subpackages are now relative;
- .mx files in the mel package have been unpacked to their constituent
  .cc (etc.) files: adding back support for C++ inside autogen was too
  hard otherwise;
- Tar balls don't include generated files (apart from configure): the
  build process, also for tar ball distributions, includes building
  and using Mx, but also now requires bison/yacc and flex/lex (there
  have been problems in the past with our distributing generated bison
  output);
- mel is only built when MonetDB4 is enabled, burg is only built when
  pathfinder is enabled;
- Some symbols in burg were replaced to avoid name clashes on Windows;
- Some files (monetdb.ico, banner.bmp, website.html, license.rtf) were
  moved to buildtools/conf;
- Use the currently approved way (by autoconf) of checking for alloca
  and alloca.h;
- Packaged vault.sql into vault.mx since autogen/Mx get confused
  otherwise;
- Set the version number globally to 11.0.0 (we need a single version
  number for binary packages, and it must be higher than the highest
  old version number).