Create basic execution environment for input code

[Hypersonic]

Code needs to execute in an environment. This environment should contain, at least:

• Variables
• A parent environment, which or none for the root environment
• A context, which is the object executing this code (an agent, the player, etc)

[Hypersonic]

On second thought, it's unnecessary to explicitly define a context for an environment. When we are executing in the context of an agent (the ask function), we can define the agent-local functions as we enter that scope. In fact, the ask function should do just that as it creates the environment in which the agent executes.