* added platform bitness handling to the build script (automatically select 32-bit or 64-bit depending on the output of "cc -dumpmachine", this should work everywhere, but can be overwritten by the "x32" or "x64" flag)
 * removed the "--" from all commands, only keep the "-" for single "-" commands; this was rather unnecessary and I don't intend to add multi-word arguments
 * cleaned up/improved the build script help output