Games with known prototypes

At some point Sega Retro will want to cover prototypes similar to Sonic Retro. This is a massive task, and puts us against Hidden Palace and The Cutting Room Floor, but we have tools they don't and Sega prototypes are within scope. Also very little coverage is better than no coverage at all.

<title> (prototype; <build date>)

They'll have sub-pages too. So this prototype of Mystic Defender for example:

• Mystic Defender (prototype; 1989-09-14)
• Mystic Defender (prototype; 1989-09-14)/Comparisons
• Mystic Defender (prototype; 1989-09-14)/Hidden content
• Mystic Defender (prototype; 1989-09-14)/Region coding

if it's more appropriate:

• Sonic the Hedgehog 2 (CENSOR prototype)

favour build dates over colloquial names where possible. Unless it makes no sense to do so.