Modernised Sord m5 driver

[dlabi]

- fd5 floppy emulation works but only with rom hack
- updated Sord m5 www links
- added fd5 utility disk to software list - not original dump, made from program listings
- added support of optional sram in Basic-F and Basic-G cartridges. Works only if shortname(softlist) is used
- marked 32/64KB RAM expansions EM-5, 64KBI, 64KBF, 64KRX as supported in sofwarelist
- reenabled and refactored memory banking
- added support of E and F block types for cassettes

- brno mod: switched to rom including basic-i
- brno mod: reenabled and refactored memory banking 

[MooglyGuy]

../../../../../src/mame/sord/m5.cpp:1092:23: error: 'void {anonymous}::m5_state::fdc_irq_timer_cb(osd::s32)' defined but not used [-Werror=unused-function]
 1092 | TIMER_CALLBACK_MEMBER(m5_state::fdc_irq_timer_cb)
      |                       ^~~~~~~~
../../../../../src/emu/schedule.h:25:46: note: in definition of macro 'TIMER_CALLBACK_MEMBER'
   25 | #define TIMER_CALLBACK_MEMBER(name)     void name(s32 param)
      |                                              ^~~~

You should probably fix this.