New buildings enable players to train wrong units

[sanderd17]

There are several buildings that, when captured by a different civ, allow the production of some unexpected unit:

• athen_dock: Shows buttons to train the marines, but other civs can never trian the marines due to a missing tech. This can confuse players.
• athen_royal_stoa: for some reason, the athenians can't train mace_thorakites in their own stoa, but if they capture another stoa (mace or spart), they would be able to train those. Any other civ capturing the stoas would also be able to produce those units. The naming of the templates for the soldiers is also confusing. It's easy to think that mace_* units can only belong to the macedonian civ, but that's not the case here.
• merc_camp_egyptian and ptol_merc_camp: both allow to train ptolemaic citizen-soldiers that give access to the complete ptolemaic building set (these are atlas-only structures).
• brit_crannog: allows the capturer to train briton citizen-soldiers and briton ships, which in turn give access to the complete briton building set.
• other/maur_palace: allows the capturer to train maurian heroes (an atlas-only structure).
• other/cart_tophet: allows capturer to train cart champions and healers (atlas-only structure).

(templates found by fatherbushido)

Setting it as release blocker, as it would harm gameplay too much to be in a release.