Plugins RFC does not handle dependencies

`rfcs/0001-plugin-index.md` presently does not incorporate any of the fields required to implement dependency management. These are the fields that are "supported" in the game, or at least currently read by the game and notionally supported:

```cpp
else if(key == "dependencies")
{
for(const DataNode &grand : child)
{
const string &grandKey = grand.Token(0);
bool grandHasValue = grand.Size() >= 2;
if(grandKey == "game version" && grandHasValue)
dependencies.gameVersion = grand.Token(1);
else if(grandKey == "requires")
for(const DataNode &great : grand)
dependencies.required.insert(great.Token(0));
else if(grandKey == "optional")
for(const DataNode &great : grand)
dependencies.optional.insert(great.Token(0));
else if(grandKey == "conflicts")
for(const DataNode &great : grand)
dependencies.conflicted.insert(great.Token(0));
else
grand.PrintTrace("Skipping unrecognized attribute:");
}
}
```