Add heavy scorpion to Byzantine

[Prokman7582]

There was a discussion that tried to investigate the possible reasons behind the Scorpion unavailability to the Byzantines:

Should Byzantines get Heavy Scorpion?

The purpose of the topic is to figure out the developer-balance reason why Byzantines don’t get Heavy Scorpion. For Byzantines, the Scorpion-line is the only in the game that they can’t upgrade to an Imperial Age relevant unit. Should this exception exist? The hint: According to AoE, Scorpion-line is “strong vs. large groups of units”, and the meta play shows that it’s better to be used vs. Infantry. It it good versus all footmen in general tho. The questions: Is the reason behind that deve…