Split into multiple pages, one per architecture

[fghsgh]

I propose splitting the Z80 and Z180 tables into two separate pages.

My main reason for this is that adding the Z180 instructions in the recent(ish) update took over the space that was previously occupied by several undocumented opcodes (namely the NEG, RETN and IM duplicates), which hinders work on real hardware as well as emulator development.

It would also provide an infrastructural solution to #1 and #2.

[deeptoaster]

That's a good point. I suppose we could have a URL structure that's something like

• /table/, /table/opcode-table.json: Z80
• /table/z180/, /table/z180/opcode-table.json: Z180
• /table/8085/, /table/8085/opcode-table.json: i8085

...and so on. Just need to actually scrape some manuals at some point...