Update rom_content.csv and syborg_stem_rom.oby with the result of the "boot_ktrace_640" reduction

Revert to the last fully working syborg_stem_rom.oby (from change fc9981c83de7)

Update bulk_marking.pl to handle the optional cmds, which was the key to making the "boot_ktrace_640" reduction work correctly

Regenerate static_dependencies.txt from first principles, to original files as well as stem_* versions

Added more things in the syborg baseport which are vital to booting the ROM

Add cmncustomcmds.dll, which is required for the shutdown list - shutdown wasn't tested in the ktrace log

Add some more vital things to make a ROM boot

Introduce prefixes "etel", "mm" and "perf" for the etel removal, the devsound removal and the hardware floating point performance optimisations

Add --options argument to pass in the (comma separated lists of) prefixes for optional "What" commands For example, the use of vfp version of OpenVG could be indicated by "vfp_Stem", in which case the alteration will only be made if "--options vfp" is included on the filter_obyfile.pl command line.

Update filter_obyfile.pl to report the "minimal ROM" executables Update bulk_marking.pl to handle lists of exes both with and without the -x option Update summarise_kerneltrace.pl to deal with the interspersed "DTimer::Create" information, and update summary.txt