PORT3 VC8 builds

Visual Studio 8 builds now supported by the build system. Also added Visual Studio 9 support and an updated C++ build specification mechanism to allow users to specify on the command line the combination of options (compiler, arch, build type) that they wish to have executed. Folded this in across HLA v1.3 and 1516e on Windows and Mac OS X.

This also now means that 32/64-bit builds are complete and being generated, however the testing suite does not yet support 64-bit and the installation generation does not package up 32/64 bit jre's together (so have a separate installer for each system).