Still porting stuff.

* Change package.d files to only import files that have module declarations in them for now.
* Implemented MondState, MondProgram, MondCompilerOptions, IndexedStack, Closure, Frame, and MondObject.
* Partially implemented MondValue.
* Add barebones definitions for DebugInfo, Machine, Parser, Expression, IBlockExpression, BlockExpression, and IStatementExpression.